Feat v0.3.6 demo workflows + interactive demo

Four example workflow packages proving the engine end-to-end:
- Bug Report Triage: public entry, branch routing, SLA timer
- Employee Onboarding: Starlark automated stages, signoff gate
- Content Approval: multi-party signoff, revision cycle loop
- Webhook Notifier: http.post, connections fallback, delivery logging

Demo surface at /s/workflow-demo with cards, stage diagrams, Starlark
viewer, API examples, active/published status, and copyable public links.

Engine fixes: started_by in automated context, sla_seconds in package
installer, parseSnapshotStages for wrapped/legacy formats.

Platform fixes: extension SDK boot in base.html (Preact globals + boot()),
admin teams paginated response extraction, workflow adoption endpoint
(POST /teams/:teamId/workflows/:id/adopt), team-admin copyable link.

Review pass remains on roadmap for remaining UI polish.

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

packages/webhook-notifier/README.md

@@ -0,0 +1,30 @@
+# Webhook Notifier
+
+Outbound webhook delivery with connection credentials and delivery logging.
+
+## Features
+
+- **Starlark `http.post`** — outbound HTTP with custom headers
+- **`connections.get`** — fallback to stored webhook connection credentials
+- **Delivery logging** — records URL, status code, event to `webhook_log` ext_data table
+- **Result review** — delivery status shown in final review stage
+
+## Stage Flow
+
+```
+[configure]  →  [fire-webhook]  →  [result]
+    team          automated          review
+                  (http.post)
+```
+
+## Starlark Hook
+
+- **`on_fire(ctx)`** — Posts JSON payload to webhook URL, falls back to `connections.get("webhook")`, logs delivery to `webhook_log`
+
+## Installation
+
+```bash
+curl -X POST $BASE/api/v1/admin/packages/install \
+  -H "Authorization: Bearer $TOKEN" \
+  -F "file=@packages/webhook-notifier"
+```