Support actions and reusable workflows from private repos (#32562)

Resolve https://gitea.com/gitea/act_runner/issues/102

This PR allows administrators of a private repository to specify some
collaborative owners. The repositories of collaborative owners will be
allowed to access this repository's actions and workflows.

Settings for private repos:


![image](https://github.com/user-attachments/assets/e591c877-f94d-48fb-82f3-3b051f21557e)

---

This PR also moves "Enable Actions" setting to `Actions > General` page

<img width="960" alt="image"
src="https://github.com/user-attachments/assets/49337ec2-afb1-4a67-8516-5c9ef0ce05d4"
/>

<img width="960" alt="image"
src="https://github.com/user-attachments/assets/f58ee6d5-17f9-4180-8760-a78e859f1c37"
/>

---------

Signed-off-by: Zettat123 <zettat123@gmail.com>
Co-authored-by: ChristopherHX <christopher.homberger@web.de>

templates/repo/settings/options.tmpl

@@ -509,18 +509,6 @@
 					</div>
 				</div>
 
-				{{if .EnableActions}}
-					{{$isActionsEnabled := .Repository.UnitEnabled ctx ctx.Consts.RepoUnitTypeActions}}
-					{{$isActionsGlobalDisabled := ctx.Consts.RepoUnitTypeActions.UnitGlobalDisabled}}
-					<div class="inline field">
-						<label>{{ctx.Locale.Tr "actions.actions"}}</label>
-							<div class="ui checkbox{{if $isActionsGlobalDisabled}} disabled{{end}}"{{if $isActionsGlobalDisabled}} data-tooltip-content="{{ctx.Locale.Tr "repo.unit_disabled"}}"{{end}}>
-							<input class="enable-system" name="enable_actions" type="checkbox" {{if $isActionsEnabled}}checked{{end}}>
-							<label>{{ctx.Locale.Tr "repo.settings.actions_desc"}}</label>
-						</div>
-					</div>
-				{{end}}
-
 				{{if not .IsMirror}}
 					<div class="divider"></div>
 					{{$pullRequestEnabled := .Repository.UnitEnabled ctx ctx.Consts.RepoUnitTypePullRequests}}