Replace #16455

Close #21803

Mixing different Gitea contexts together causes some problems:

1. Unable to respond proper content when error occurs, eg: Web should
respond HTML while API should respond JSON
2. Unclear dependency, eg: it's unclear when Context is used in
APIContext, which fields should be initialized, which methods are
necessary.


To make things clear, this PR introduces a Base context, it only
provides basic Req/Resp/Data features.

This PR mainly moves code. There are still many legacy problems and
TODOs in code, leave unrelated changes to future PRs.

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>

Add nakedret, unconvert, wastedassign, stylecheck and nolintlint linters to improve code readability

- nakedret - https://github.com/alexkohler/nakedret - nakedret is a Go static analysis tool to find naked returns in functions greater than a specified function length.
- unconvert - https://github.com/mdempsky/unconvert - Remove unnecessary type conversions
- wastedassign - https://github.com/sanposhiho/wastedassign -  wastedassign finds wasted assignment statements.
- notlintlint -  Reports ill-formed or insufficient nolint directives
- stylecheck - https://staticcheck.io/docs/checks/#ST - keep style consistent
  - excluded: [ST1003 - Poorly chosen identifier](https://staticcheck.io/docs/checks/#ST1003) and [ST1005 - Incorrectly formatted error string](https://staticcheck.io/docs/checks/#ST1005)

Reusing `/api/v1` from Gitea UI Pages have pros and cons.
Pros:
1) Less code copy

Cons:
1) API/v1 have to support shared session with page requests.
2) You need to consider for each other when you want to change something about api/v1 or page.

This PR moves all dependencies to API/v1 from UI Pages.

Partially replace #16052

* Move login related structs and functions to models/login

* Fix test

* Fix lint

* Fix lint

* Fix lint of windows

* Fix lint

* Fix test

* Fix test

* Only load necessary fixtures when preparing unit tests envs

* Fix lint

* Fix test

* Fix test

* Fix error log

* Fix error log

* Fix error log

* remove unnecessary change

* fix error log

* merge main branch

Followup from #16562 prepare for #16567

* Rename ctx.Form() to ctx.FormString()
* Reimplement FormX func to need less code and cpu cycles
* Move code into own file

* Repository object only count releases as releases (fix #16144)

* EditOrg respect RepoAdminChangeTeamAccess option (fix #16013)

* make PaginateUserSlice generic -> PaginateSlice

* Add pagination to ListBranches

* add skip, limit to Repository.GetBranches()

* Move routers/api/v1/utils/utils PaginateSlice -> modules/util/paginate.go

* repo_module.GetBranches paginate

* fix & rename & more logging

* better description

Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: a101211279 <1012112796@qq.com>

* HotFix: Hide private partisipation in Orgs

* refactor & add node to fuc GetOrganizations

* remove ReplaceLeft

* remove GetRepositoryByOwnerAndName chainload to models.GetRepositoryByOwnerAndName

* remove CheckUnitUser chainload to models.CheckUnitUser

* remove MakeAssigneeList

* remove DownloadDiff & DownloadPatch -> DownloadDiffOrPatch

* remove GetRandomBytesAsBase64

* remove PushUpdateDeleteTags

* remove GetUserByKeyID
(you still can resolve user by "k, err := GetPublicKeyByID; userID := k.OwnerID")

* remove BasicAuthEncode from struct package -> same function in modules/base/tools !

* remove UserID from api.utils

* remove unused func from structs package

* paginate results

* fixed deadlock

* prevented breaking change

* updated swagger

* go fmt

* fixed find topic

* go mod tidy

* go mod vendor with go1.13.5

* fixed repo find topics

* fixed unit test

* added Limit method to Engine struct; use engine variable when provided; fixed gitignore

* use ItemsPerPage for default pagesize; fix GetWatchers, getOrgUsersByOrgID and GetStargazers; fix GetAllCommits headers; reverted some changed behaviors

* set Page value on Home route

* improved memory allocations

* fixed response headers

* removed logfiles

* fixed import order

* import order

* improved swagger

* added function to get models.ListOptions from context

* removed pagesize diff on unit test

* fixed imports

* removed unnecessary struct field

* fixed go fmt

* scoped PR

* code improvements

* code improvements

* go mod tidy

* fixed import order

* fixed commit statuses session

* fixed files headers

* fixed headers; added pagination for notifications

* go mod tidy

* go fmt

* removed Private from user search options; added setting.UI.IssuePagingNum as default valeu on repo's issues list

* Apply suggestions from code review

Co-Authored-By: 6543 <6543@obermui.de>
Co-Authored-By: zeripath <art27@cantab.net>

* fixed build error

* CI.restart()

* fixed merge conflicts resolve

* fixed conflicts resolve

* improved FindTrackedTimesOptions.ToOptions() method

* added backwards compatibility on ListReleases request; fixed issue tracked time ToSession

* fixed build error; fixed swagger template

* fixed swagger template

* fixed ListReleases backwards compatibility

* added page to user search route

Co-authored-by: techknowlogick <matti@mdranta.net>
Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: zeripath <art27@cantab.net>

(extend #9200)
 * add query param for GET functions (created Bevore & after)
 * add test
 * generalize func GetQueryBeforeSince

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

Don't require token when not necessary