agents: review round 2 — split-PR flow, thread recency, mention boundaries, learnings cap, pm model

- publish.sh: resolve_prs matches ai/issue-N AND ai/issue-N-<slug> split branches
  (exact-only silently stalled DELEGATE:@qa and autopilot MERGE_PR on slugged
  work); qa hand-off lists all open PRs; autopilot refuses to merge multi-PR
  issues (drops the label, hands to the human) — merging one of several open
  PRs is half a change deployed. Retro's state=all resolve matches slugs too.
- fetch-thread.sh: paginate and keep the NEWEST 100 comments — a bare limit=100
  kept the OLDEST page and dropped recent decisions on long threads.
- route.sh: word-boundary mention matching ("@internal" no longer routes to
  @intern); a comment with no real agent mention now SKIPS gracefully
  (mode=skip outputs + step guards in agent.yml) instead of a red run.
- run-agent.sh: LEARNINGS.md cap is line-aware and keeps the NEWEST entries
  (retros append at the bottom; the old head -c cut the latest lessons first).
- agents.json/README: @pm gemma4 -> minimax-m3 — the retro rule demands an
  investigating PM, and gemma4 posted 0 tool calls on every run; minimax is the
  model @qa demonstrably uses tools with.
- agent.yml: document the PR-thread concurrency-group caveat.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitea/workflows/scripts/run-agent.sh

@@ -109,8 +109,18 @@ fi
 # TEAM LEARNINGS — distilled from past retros (see the RETRO flow in publish.sh). Lives at the
 # CALLER repo root as LEARNINGS.md, maintained by retro PRs. Injected into EVERY agent's prompt
 # (capped) so past mistakes actually change future behavior — this is the feedback loop.
+# Cap is LINE-aware and keeps the NEWEST entries: retros append at the bottom, so a byte-cap from
+# the top would silently drop the latest lessons first (and cut mid-bullet).
 LEARN=""
-[ -s LEARNINGS.md ] && LEARN=$(head -c 4000 LEARNINGS.md)
+if [ -s LEARNINGS.md ]; then
+  if [ "$(wc -l < LEARNINGS.md)" -gt 80 ]; then
+    LEARN=$(printf '%s\n_(older learnings truncated — full list in LEARNINGS.md)_\n%s' \
+      "$(head -n 3 LEARNINGS.md)" "$(tail -n 70 LEARNINGS.md)")
+  else
+    LEARN=$(cat LEARNINGS.md)
+  fi
+  LEARN=$(printf '%s' "$LEARN" | head -c 8000)
+fi
 [ -n "$LEARN" ] && LEARN="
    TEAM LEARNINGS (distilled from past retros in this repo — APPLY them; they exist because a
    previous task went wrong without them):