enhance(actions): Make Summary UI more beautiful with more infos (#37824)

## Summary

- Redesign the Actions run summary header to follow GitHub Actions
layout: trigger info on the left, Status / Total duration / Artifacts
columns inline on the right
- Expose trigger user avatar, pull request link, and PR head branch info
from the run view API
- Update the workflow graph header to show the workflow filename (linked
to the run workflow file) and `on: <event>`, while keeping the
jobs/dependencies/success stats line
- Remove the redundant commit/workflow metadata row below the run title;
that information now lives in the summary bar

New:
<img width="1564" height="639"
src="https://github.com/user-attachments/assets/e6bc1623-c5fc-4e97-abc9-fde7f3c6aef9"
/>

Old:
<img width="2038" height="1038"
src="https://github.com/user-attachments/assets/0857f19a-8d3a-4da2-82fd-e9ebeb200062"
/>

Replaces https://github.com/go-gitea/gitea/pull/36721

---------

Co-authored-by: Giteabot <teabot@gitea.io>

options/locale/locale_en-US.json

@@ -3804,7 +3804,10 @@
   "actions.runs.latest": "Latest",
   "actions.runs.latest_attempt": "Latest attempt",
   "actions.runs.triggered_via": "Triggered via %s",
-  "actions.runs.total_duration": "Total duration:",
+  "actions.runs.rerun_triggered": "Re-run triggered",
+  "actions.runs.back_to_pull_request": "Back to pull request",
+  "actions.runs.back_to_workflow": "Back to workflow",
+  "actions.runs.total_duration": "Total duration",
   "actions.runs.workflow_dependencies": "Workflow Dependencies",
   "actions.runs.graph_jobs_count_1": "%d job",
   "actions.runs.graph_jobs_count_n": "%d jobs",