* Refactor AssertExistsAndLoadBean to use generics

* Fix tests

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

* 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 access and repo permission to models/perm/access

* fix test

* Move some git related files into sub package models/git

* Fix build

* fix git test

* move lfs to sub package

* move more git related functions to models/git

* Move functions sequence

* Some improvements per @KN4CK3R and @delvh

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

... more context

(part of #9307)

make more usage of context, to have more db transaction in one session

(make diff of  #9307 smaller)

* Use a struct as test options

* Fix name

* Fix test

Follows #19266, #8553, Close #18553, now there are only three `Run..(&RunOpts{})` functions.
 * before: `stdout, err := RunInDir(path)`
 * now: `stdout, _, err := RunStdString(&git.RunOpts{Dir:path})`

* OpenRepositoryCtx -> OpenRepository
* OpenRepository -> openRepositoryWithDefaultContext, only for internal usage

* Remove `db.DefaultContext` usage in routers, use `ctx` directly

* Use `ctx` directly if there is one, remove some `db.DefaultContext` in `services`

* Use ctx instead of db.DefaultContext for `cmd` and some `modules` packages

* fix incorrect context usage

This PR continues the work in #17125 by progressively ensuring that git
commands run within the request context.

This now means that the if there is a git repo already open in the context it will be used instead of reopening it.

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

* Add missing `X-Total-Count` and fix some related bugs

Adds `X-Total-Count` header to APIs that return a list but doesn't have it yet.
Fixed bugs:
* not returned after reporting error (39eb82446c/routers/api/v1/user/star.go (L70))
* crash with index out of bounds, API issue/issueSubscriptions

I also found various endpoints that return lists but do not apply/support pagination yet:
```
/repos/{owner}/{repo}/issues/{index}/labels
/repos/{owner}/{repo}/issues/comments/{id}/reactions
/repos/{owner}/{repo}/branch_protections
/repos/{owner}/{repo}/contents
/repos/{owner}/{repo}/hooks/git
/repos/{owner}/{repo}/issue_templates
/repos/{owner}/{repo}/releases/{id}/assets
/repos/{owner}/{repo}/reviewers
/repos/{owner}/{repo}/teams
/user/emails
/users/{username}/heatmap
```
If this is not expected, an new issue should be opened.

Closes #13043

* fmt

* Update routers/api/v1/repo/issue_subscription.go

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>

* Use FindAndCount

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>
Co-authored-by: 6543 <6543@obermui.de>

* Move keys to models/keys

* Rename models/keys -> models/asymkey

* change the missed package name

* Fix package alias

* Fix test

* Fix docs

* Fix test

* Fix test

* merge