Upgrade agentic workflows from gh-aw v0.72.1 to v0.80.9 (#2092)

- Recompile all 6 workflow lock files with gh-aw v0.80.9
- Update gh-aw-actions/setup v0.72.1 → v0.80.9
- Update actions/checkout v6.0.2 → v7.0.0
- Refresh container image pins across all workflows
- Fix learning-hub-updater.md: add missing permissions.contents: read
  (root cause of safe_outputs 'Failed to apply bundle' failures)
- Update dispatcher SKILL.md and agentic-workflows agent
- Update actions-lock.json and copilot-setup-steps.yml

Fixes: #2077 (learning-hub-updater), #2080 (cli-for-beginners-sync)
Part of: #2076

Co-authored-by: Ayan Gupta <ayangupta@Ayans-MacBook-Pro.local>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

.github/workflows/learning-hub-updater.md

@@ -4,6 +4,8 @@ description: "Daily check for new GitHub Copilot features and updates. Opens a P
 on:
   schedule: daily
   workflow_dispatch:
+permissions:
+  contents: read
 tools:
   bash: ["curl", "gh"]
   edit:
@@ -83,4 +85,4 @@ Create a pull request with your changes, using the `staged` branch as the base b
 2. What sections of the guide were updated
 3. Links to the source announcements
 
-The PR should target the `staged` branch and include the labels `automated-update` and `copilot-updates`.
+The PR should target the `staged` branch and include the labels `automated-update` and `copilot-updates`.