Support scoped access tokens (#20908)

This PR adds the support for scopes of access tokens, mimicking the
design of GitHub OAuth scopes.

The changes of the core logic are in `models/auth` that `AccessToken`
struct will have a `Scope` field. The normalized (no duplication of
scope), comma-separated scope string will be stored in `access_token`
table in the database.
In `services/auth`, the scope will be stored in context, which will be
used by `reqToken` middleware in API calls. Only OAuth2 tokens will have
granular token scopes, while others like BasicAuth will default to scope
`all`.
A large amount of work happens in `routers/api/v1/api.go` and the
corresponding `tests/integration` tests, that is adding necessary scopes
to each of the API calls as they fit.


- [x] Add `Scope` field to `AccessToken`
- [x] Add access control to all API endpoints
- [x] Update frontend & backend for when creating tokens
- [x] Add a database migration for `scope` column (enable 'all' access
to past tokens)

I'm aiming to complete it before Gitea 1.19 release.

Fixes #4300

tests/integration/api_packages_container_test.go

@@ -13,6 +13,7 @@ import (
 	"sync"
 	"testing"
 
+	auth_model "code.gitea.io/gitea/models/auth"
 	"code.gitea.io/gitea/models/db"
 	packages_model "code.gitea.io/gitea/models/packages"
 	container_model "code.gitea.io/gitea/models/packages/container"
@@ -31,6 +32,8 @@ func TestPackageContainer(t *testing.T) {
 	defer tests.PrepareTestEnv(t)()
 
 	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+	session := loginUser(t, user.Name)
+	token := getTokenForLoggedInUser(t, session, auth_model.AccessTokenScopeReadPackage)
 
 	has := func(l packages_model.PackagePropertyList, name string) bool {
 		for _, pp := range l {
@@ -558,7 +561,7 @@ func TestPackageContainer(t *testing.T) {
 					assert.Equal(t, c.ExpectedLink, resp.Header().Get("Link"))
 				}
 
-				req := NewRequest(t, "GET", fmt.Sprintf("/api/v1/packages/%s?type=container&q=%s", user.Name, image))
+				req := NewRequest(t, "GET", fmt.Sprintf("/api/v1/packages/%s?type=container&q=%s&token=%s", user.Name, image, token))
 				resp := MakeRequest(t, req, http.StatusOK)
 
 				var apiPackages []*api.Package