Rescue work from claudomator-work: question/answer, ratelimit, start-next-task

Merges features developed in /site/doot.terst.org/claudomator-work (a
stale clone) into the canonical repo:

- executor: QuestionRegistry for human-in-the-loop answers, rate limit
  detection and exponential backoff retry (ratelimit.go, question.go)
- executor/claude.go: process group isolation (SIGKILL orphans on cancel),
  os.Pipe for reliable stdout drain, backoff retry on rate limits
- api/scripts.go: POST /api/scripts/start-next-task handler
- api/server.go: startNextTaskScript field, answer-question route,
  BroadcastQuestion for WebSocket question events
- web: Cancel/Restart buttons, question banner UI, log viewer, validate
  section, WebSocket auto-connect

All tests pass.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/web/index.html b/web/index.html
index 6d7f23b..482b9a9 100644
--- a/web/index.html
+++ b/web/index.html
@@ -50,6 +50,12 @@
       <hr class="form-divider">
       <label>Name <input name="name" required></label>
       <label>Instructions <textarea name="instructions" rows="6" required></textarea></label>
+      <div class="validate-section">
+        <button type="button" id="btn-validate" class="btn-secondary">
+          Validate Instructions
+        </button>
+        <div id="validate-result" hidden></div>
+      </div>
       <label>Working Directory <input name="working_dir" placeholder="/path/to/repo"></label>
       <label>Model <input name="model" value="sonnet"></label>
       <label>Max Budget (USD) <input name="max_budget_usd" type="number" step="0.01" value="1.00"></label>