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>

web_src/js/svg.ts

@@ -7,6 +7,7 @@ import giteaEmptyCheckbox from '../../public/assets/img/svg/gitea-empty-checkbox
 import giteaExclamation from '../../public/assets/img/svg/gitea-exclamation.svg';
 import giteaRunning from '../../public/assets/img/svg/gitea-running.svg';
 import octiconArchive from '../../public/assets/img/svg/octicon-archive.svg';
+import octiconArrowLeft from '../../public/assets/img/svg/octicon-arrow-left.svg';
 import octiconArrowSwitch from '../../public/assets/img/svg/octicon-arrow-switch.svg';
 import octiconBlocked from '../../public/assets/img/svg/octicon-blocked.svg';
 import octiconBold from '../../public/assets/img/svg/octicon-bold.svg';
@@ -94,6 +95,7 @@ const svgs = {
   'gitea-exclamation': giteaExclamation,
   'gitea-running': giteaRunning,
   'octicon-archive': octiconArchive,
+  'octicon-arrow-left': octiconArrowLeft,
   'octicon-arrow-switch': octiconArrowSwitch,
   'octicon-blocked': octiconBlocked,
   'octicon-bold': octiconBold,