Close #13539.

Co-authored by: @lunny @appleboy @fuxiaohei and others.

Related projects:
- https://gitea.com/gitea/actions-proto-def
- https://gitea.com/gitea/actions-proto-go
- https://gitea.com/gitea/act
- https://gitea.com/gitea/act_runner

### Summary

The target of this PR is to bring a basic implementation of "Actions",
an internal CI/CD system of Gitea. That means even though it has been
merged, the state of the feature is **EXPERIMENTAL**, and please note
that:

- It is disabled by default;
- It shouldn't be used in a production environment currently;
- It shouldn't be used in a public Gitea instance currently;
- Breaking changes may be made before it's stable.

**Please comment on #13539 if you have any different product design
ideas**, all decisions reached there will be adopted here. But in this
PR, we don't talk about **naming, feature-creep or alternatives**.

### ⚠️ Breaking

`gitea-actions` will become a reserved user name. If a user with the
name already exists in the database, it is recommended to rename it.

### Some important reviews

- What is `DEFAULT_ACTIONS_URL` in `app.ini` for?
  - https://github.com/go-gitea/gitea/pull/21937#discussion_r1055954954
- Why the api for runners is not under the normal `/api/v1` prefix?
  - https://github.com/go-gitea/gitea/pull/21937#discussion_r1061173592
- Why DBFS?
  - https://github.com/go-gitea/gitea/pull/21937#discussion_r1061301178
- Why ignore events triggered by `gitea-actions` bot?
  - https://github.com/go-gitea/gitea/pull/21937#discussion_r1063254103
- Why there's no permission control for actions?
  - https://github.com/go-gitea/gitea/pull/21937#discussion_r1090229868

### What it looks like

<details>

#### Manage runners

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205870657-c72f590e-2e08-4cd4-be7f-2e0abb299bbf.png">

#### List runs

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205872794-50fde990-2b45-48c1-a178-908e4ec5b627.png">


#### View logs

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205872501-9b7b9000-9542-4991-8f55-18ccdada77c3.png">



</details>

### How to try it

<details>

#### 1. Start Gitea

Clone this branch and [install from
source](https://docs.gitea.io/en-us/install-from-source).

Add additional configurations in `app.ini` to enable Actions:

```ini
[actions]
ENABLED = true
```

Start it.

If all is well, you'll see the management page of runners:

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205877365-8e30a780-9b10-4154-b3e8-ee6c3cb35a59.png">


#### 2. Start runner

Clone the [act_runner](https://gitea.com/gitea/act_runner), and follow
the
[README](https://gitea.com/gitea/act_runner/src/branch/main/README.md)
to start it.

If all is well, you'll see a new runner has been added:

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205878000-216f5937-e696-470d-b66c-8473987d91c3.png">

#### 3. Enable actions for a repo

Create a new repo or open an existing one, check the `Actions` checkbox
in settings and submit.

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205879705-53e09208-73c0-4b3e-a123-2dcf9aba4b9c.png">
<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205879383-23f3d08f-1a85-41dd-a8b3-54e2ee6453e8.png">

If all is well, you'll see a new tab "Actions":

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205881648-a8072d8c-5803-4d76-b8a8-9b2fb49516c1.png">

#### 4. Upload workflow files

Upload some workflow files to `.gitea/workflows/xxx.yaml`, you can
follow the [quickstart](https://docs.github.com/en/actions/quickstart)
of GitHub Actions. Yes, Gitea Actions is compatible with GitHub Actions
in most cases, you can use the same demo:

```yaml
name: GitHub Actions Demo
run-name: ${{ github.actor }} is testing out GitHub Actions 🚀
on: [push]
jobs:
  Explore-GitHub-Actions:
    runs-on: ubuntu-latest
    steps:
      - run: echo "🎉 The job was automatically triggered by a ${{ github.event_name }} event."
      - run: echo "🐧 This job is now running on a ${{ runner.os }} server hosted by GitHub!"
      - run: echo "🔎 The name of your branch is ${{ github.ref }} and your repository is ${{ github.repository }}."
      - name: Check out repository code
        uses: actions/checkout@v3
      - run: echo "💡 The ${{ github.repository }} repository has been cloned to the runner."
      - run: echo "🖥️ The workflow is now ready to test your code on the runner."
      - name: List files in the repository
        run: |
          ls ${{ github.workspace }}
      - run: echo "🍏 This job's status is ${{ job.status }}."
```

If all is well, you'll see a new run in `Actions` tab:

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205884473-79a874bc-171b-4aaf-acd5-0241a45c3b53.png">

#### 5. Check the logs of jobs

Click a run and you'll see the logs:

<img width="1792" alt="image"
src="https://user-images.githubusercontent.com/9418365/205884800-994b0374-67f7-48ff-be9a-4c53f3141547.png">

#### 6. Go on

You can try more examples in [the
documents](https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions)
of GitHub Actions, then you might find a lot of bugs.

Come on, PRs are welcome.

</details>

See also: [Feature Preview: Gitea
Actions](https://blog.gitea.io/2022/12/feature-preview-gitea-actions/)

---------

Co-authored-by: a101211279 <1012112796@qq.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: ChristopherHX <christopher.homberger@web.de>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>

Change all license headers to comply with REUSE specification.

Fix #16132

Co-authored-by: flynnnnnnnnnn <flynnnnnnnnnn@github>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>

This PR adds a context parameter to a bunch of methods. Some helper
`xxxCtx()` methods got replaced with the normal name now.

Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

Found using
`find . -type f -name '*.go' -print -exec vim {} -c
':%s/fmt\.Errorf(\(.*\)%v\(.*\)err/fmt.Errorf(\1%w\2err/g' -c ':wq' \;`

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

This PR adds a generic set type to get rid of maps used as sets.

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

Co-authored-by: lukas <lukas.walter@aceart.de>

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

* Move access and repo permission to models/perm/access

* fix test

* fix git test

* Move functions sequence

* Some improvements per @KN4CK3R and @delvh

* Move issues related code to models/issues

* Move some issues related sub package

* Merge

* Fix test

* Fix test

* Fix test

* Fix test

* Rename some files

* Move some repository related code into sub package

* Move more repository functions out of models

* Fix lint

* Some performance optimization for webhooks and others

* some refactors

* Fix lint

* Fix

* Update modules/repository/delete.go

Co-authored-by: delvh <dev.lh@web.de>

* Fix test

* Merge

* Fix test

* Fix test

* Fix test

* Fix test

Co-authored-by: delvh <dev.lh@web.de>

Add ability to show source/target branches for Pull Request's list. It can be useful to see which branches are used in each PR right in the list.

Co-authored-by: Alexey Korobkov <akorobkov@cian.ru>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Lauris BH <lauris@nix.lv>

* Move almost all functions' parameter db.Engine to context.Context
* remove some unnecessary wrap functions

* Move milestone to models/issues/

* Fix lint

* Fix test

* Fix lint

* Fix lint

* Move reaction to models/issues/

* Fix test

* move the function

* improve code

* Update models/issues/reaction.go

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

* Use conditions but not repo ids as query condition

* Improve the performance of pulls/issue

* Remove duplicated code

* fix lint

* Fix bug

* Fix stats

* More fixes

* Fix build

* Fix lint

* Fix test

* Fix build

* Adjust the logic

* Merge

* Fix conflicts

* improve the performance

* Add comments for the query conditions functions

* Some improvements

* Some refactors related repository model

* Move more methods out of repository

* Move repository into models/repo

* Fix test

* Fix test

* some improvements

* Remove unnecessary function

* Move user related model into models/user

* Fix lint for windows

* Fix windows lint

* Fix windows lint

* Move some tests in models

* Merge

* Move attachment into models/repo/

* Fix test

* Fix bug

* go build / format tools
* re-format imports

* DBContext is just a Context

This PR removes some of the specialness from the DBContext and makes it context
This allows us to simplify the GetEngine code to wrap around any context in future
and means that we can change our loadRepo(e Engine) functions to simply take contexts.

Signed-off-by: Andrew Thornton <art27@cantab.net>

* fix unit tests

Signed-off-by: Andrew Thornton <art27@cantab.net>

* another place that needs to set the initial context

Signed-off-by: Andrew Thornton <art27@cantab.net>

* avoid race

Signed-off-by: Andrew Thornton <art27@cantab.net>

* change attachment error

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Move db related basic functions to models/db

* Fix lint

* Fix lint

* Fix test

* Fix lint

* Fix lint

* revert unnecessary change

* Fix test

* Fix wrong replace string

* Use *Context

* Correct committer spelling and fix wrong replaced words

Co-authored-by: zeripath <art27@cantab.net>

* chore: rewrite format.

* chore: update format

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

* chore: update format

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

* chore: Adjacent parameters with the same type should be grouped together

* chore: update format.

* Add dismiss review feature

refs:
    https://github.blog/2016-10-12-dismissing-reviews-on-pull-requests/
    https://developer.github.com/v3/pulls/reviews/#dismiss-a-review-for-a-pull-request

* change modal ui and error message

* Add unDismissReview api

Signed-off-by: a101211279 <1012112796@qq.com>
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: 6543 <6543@obermui.de>

* FIX by simplify

* code reformat and optimize

* Add Approval Counts to pulls list

Add simple approvals counts to pulls lists

* Remove non-official counts

* Add PR features to milestone_issues.tmpl

Extensively extend the times API.

close #8833; close #8513; close #8559

* fix error log when loading issues caused by a xorm bug

* upgrade packages

* fix fmt

* fix Consistency

* fix tests

* Show total tracked time in issue and milestone list
Show total tracked time at issue page

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Optimizing TotalTimes by using SumInt

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Fixing wrong total times for milestones caused by a missing JOIN
Adding unit tests for total times

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Logging error instead of ignoring it

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Correcting spelling mistakes

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Change error message to a short version

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Add error handling to TotalTimes
Add variable for totalTimes

Signed-off-by: Jonas Franz <info@jonasfranz.de>

* Introduce TotalTrackedTimes as variable of issue
Load TotalTrackedTimes by loading attributes of IssueList
Load TotalTrackedTimes by loading attributes of single issue
Add Sec2Time as helper to use it in templates

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Fixed test + gofmt

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Load TotalTrackedTimes via MilestoneList instead of single requests

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Add documentation for MilestoneList

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Add documentation for MilestoneList

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Fix test

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Change comment from SQL query to description

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Fix unit test by using int64 instead of int

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Fix unit test by using int64 instead of int

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Check if timetracker is enabled

Signed-off-by: Jonas Franz <info@jonasfranz.software>

* Fix test by enabling timetracking

Signed-off-by: Jonas Franz <info@jonasfranz.de>

Fix bug where unassigned issues would appear to be assigned to a ghost user

* refactor for issues loadattributes of a repository

* refactors