refactor: simplify trigger server to fire-and-forget + fix monitoring loop prompts (#1384)

The trigger server streamed script stdout back to GitHub Actions via a
long-lived HTTP response, requiring --http1.1, heartbeat injection,
server.timeout(req, 0), createEnqueuer, drainStreamOutput, and 90-min
GH Actions timeouts. In practice GitHub Actions is just a dumb trigger
— the real state lives on the VM (log files, journalctl). Simplify to
fire-and-forget: spawn script, return 200 JSON immediately.

Also fix the refactor and discovery team lead monitoring loops. The
prompts buried the loop in a single compressed line that the model
ignored (doing Bash("sleep 10") repeatedly without calling TaskList).
Replace with a dedicated "Monitor Loop (CRITICAL)" section with numbered
steps, matching the security.sh pattern that actually works.

Changes:
- trigger-server.ts: remove ~150 lines of streaming code (createEnqueuer,
  drainStreamOutput, startStreamingRun, heartbeat, ReadableStream),
  replace with startFireAndForgetRun (stdout: "inherit", immediate JSON)
- All 4 workflows: simple curl POST, timeout-minutes 90→5, remove
  --http1.1/-N/--max-time/exit-code handling
- refactor.sh: add Monitor Loop (CRITICAL) section with numbered steps
- discovery-team-prompt.txt: same Monitor Loop fix
- SKILL.md: update architecture docs, remove streaming sections

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/workflows/qa.yml

@@ -9,13 +9,13 @@ concurrency:
 jobs:
   trigger:
     runs-on: ubuntu-latest
-    timeout-minutes: 90
+    timeout-minutes: 5
     steps:
-      - name: Trigger QA cycle on Sprite
+      - name: Trigger QA cycle
         env:
           SPRITE_URL: ${{ secrets.QA_SPRITE_URL }}
           TRIGGER_SECRET: ${{ secrets.QA_TRIGGER_SECRET }}
         run: |
-          curl -sSN --fail-with-body --max-time 5400 -X POST \
+          curl -sS --fail-with-body -X POST \
             "${SPRITE_URL}/trigger?reason=${{ github.event_name }}" \
             -H "Authorization: Bearer ${TRIGGER_SECRET}"