feat(actions): add job summaries (GITHUB_STEP_SUMMARY) (#37500)

- Add GitHub-style Actions **job summaries** support
(`GITHUB_STEP_SUMMARY` / `workflow/SUMMARY.md`) and render them on the
run Summary view.
- Store uploaded summaries internally in the DB (not as downloadable
artifacts).
- Add runtime-token endpoint for runners to upload summaries:
- `PUT
/api/actions_pipeline/_apis/pipelines/workflows/{run_id}/jobs/{job_id}/summary`
- Advertise support to runners via `RunnerService.Declare` response
header:
  - `X-Gitea-Actions-Capabilities: job-summary`
- Devtest: extend `/devtest/repo-action-view/...` to include mock
`jobSummaries` for previewing UI rendering.

## Compatibility
- New Gitea + old runner: no summary upload → UI shows nothing (no
behavior change)
- New runner + old Gitea: capability not advertised → runner skips
upload (no behavior change)

## Screenshot:

<img width="2017" height="729"
src="https://github.com/user-attachments/assets/31f8b945-50c4-40e1-9f40-382901a53013"
/>


Fixes #23721
PR on gitea-runner https://gitea.com/gitea/runner/pulls/917

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Claude (Opus 4.7) <noreply@anthropic.com>

services/actions/cleanup.go

@@ -232,6 +232,10 @@ func DeleteRun(ctx context.Context, run *actions_model.ActionRun) error {
 		RepoID: repoID,
 		RunID:  run.ID,
 	})
+	recordsToDelete = append(recordsToDelete, &actions_model.ActionRunJobSummary{
+		RepoID: repoID,
+		RunID:  run.ID,
+	})
 
 	if err := db.WithTx(ctx, func(ctx context.Context) error {
 		// TODO: Deleting task records could break current ephemeral runner implementation. This is a temporary workaround suggested by ChristopherHX.

services/repository/delete.go

@@ -177,6 +177,7 @@ func DeleteRepositoryDirectly(ctx context.Context, repoID int64, ignoreOrgTeams
 		&actions_model.ActionScheduleSpec{RepoID: repoID},
 		&actions_model.ActionSchedule{RepoID: repoID},
 		&actions_model.ActionArtifact{RepoID: repoID},
+		&actions_model.ActionRunJobSummary{RepoID: repoID},
 		&actions_model.ActionRunnerToken{RepoID: repoID},
 		&issues_model.IssuePin{RepoID: repoID},
 	); err != nil {