Add Gitea/GitHub CI pipeline, QA deploy, and Husky pre-push hook

Builds and tests are driven entirely by scripts/ci/*.sh so every step
(build, test, image build/push, QA deploy) can be run identically in
CI or on a workstation. QA runs as an isolated docker-compose stack
with its Postgres volume wiped and recreated on each deploy.

deploy/qa/.env.example

@@ -0,0 +1,12 @@
+# Copy to .env (or export in CI) and fill in real values.
+# Used by scripts/ci/*.sh and deploy/qa/docker-compose.qa.yml.
+
+# Gitea container registry
+REGISTRY=gitea.example.com
+REGISTRY_OWNER=your-org-or-user
+REGISTRY_USER=ci-bot
+REGISTRY_TOKEN=changeme
+
+# QA environment
+JWT_SECRET_KEY=change-this-to-a-random-32-plus-char-secret
+QA_ADMIN_PORT=3001