ci(panels): pin target=copilot for pr-review-panel and triage-panel (#1192)

Both panels run on the gh-aw default Copilot CLI engine, so they only
need the 'copilot' layout from the apm package. Pinning target=copilot
(via the new shared/apm.md input from #1184) ships a slim per-harness
bundle instead of installing all seven harnesses on every panel run.

This also side-steps the cowork-in-all crash that hit the apm
self-check (run 25511043293) before #1191 landed; the panels now
explicitly request a single supported harness, so an experimental
target leaking into 'all' could not regress these workflows again.

Co-authored-by: Daniel Meppiel <copilot-rework@github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 3 people

.github/workflows/pr-review-panel.lock.yml

@@ -87,6 +87,7 @@ permissions:
 imports:
   - uses: shared/apm.md
     with:
+      target: copilot
       packages:
         - microsoft/apm#main
 

.github/workflows/pr-review-panel.md

@@ -98,6 +98,7 @@ permissions:
 imports:
   - uses: shared/apm.md
     with:
+      target: copilot
       packages:
         - microsoft/apm#main