Upgrade HeyForm from v0.1.0 to v3.0.5

v0.1.0 (Feb 2025) has dozens of published security advisories fixed in
v3. Tested against a copy of the database first; forms load unchanged.

v3 listens on 9157, keeps uploads under packages/server, and uses Redis 8
commands, so KeyDB is replaced by redis:8-alpine. The homepage URL is now
https (v3's CORS allowlist is built from it), Caddy is the trusted proxy,
public sign-up is off, and integration credentials get their own key.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

roles/docker/tasks/productivity/heyform.yml

@@ -17,4 +17,5 @@
   community.docker.docker_compose_v2:
     project_src: /opt/stacks/heyform
     files:
-    - compose.yml
+    - compose.yml
+    remove_orphans: true  # KeyDB was replaced by Redis