feat(drone): enroll drone + gitea SCM dep (M1 implementation)

- tests/gitea/recipe_meta.py: gitea as install-time dep provider; sqlite3
  overlay EXTRA_ENV, health path /api/healthz, relaxed access for CI use
- tests/drone/recipe_meta.py: DEPS=["gitea"]; health /healthz; 600s timeout
- tests/drone/install_steps.sh: wires GITEA_CLIENT_ID + GITEA_DOMAIN +
  client_secret Docker secret + DRONE_USER_CREATE before single drone deploy
- tests/drone/functional/test_scm_configured.py: Playwright-free SCM test —
  follows /login redirect, asserts final URL is gitea dep's OAuth2 authorize
  endpoint with matching client_id (per Adversary pre-probe REVIEW-drone.md)
- tests/drone/PARITY.md: backup structural-skip justified (no backupbot labels)
- runner/harness/sso.py: setup_gitea_oauth() — creates gitea admin user via
  CLI + OAuth2 app via API, returns {admin_user, admin_password, client_id,
  client_secret} for install_steps.sh consumption
- runner/run_recipe_ci.py: _enrich_deps_with_sso now handles gitea dep (calls
  setup_gitea_oauth; keycloak path unchanged)
- tests/unit/test_gitea_dep.py: unit tests for gitea dep path — meta loading,
  SSO routing, SCM redirect assertion logic (parametrized)
- machine-docs: STATUS/JOURNAL/BACKLOG-drone.md phase state files initialized

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

machine-docs/JOURNAL-drone.md

@@ -0,0 +1,59 @@
+# JOURNAL — phase drone (drone enrollment with gitea SCM dep)
+
+**Phase plan:** `/srv/cc-ci/cc-ci-plan/plan-phase-drone-enroll.md`
+**Builder:** autonomic-bot / Claude
+
+---
+
+## 2026-06-11 — Phase start + design decisions
+
+### Context read
+- P0 confirmed: `/etc/timezone` exists (UTC) on cc-ci host — fix from commit 3bde76f is live
+- Adversary pre-probes read from REVIEW-drone.md:
+  - Confirms P0 satisfied
+  - Confirms drone 1.9.0+2.26.0 (latest), 1.8.0+2.25.0 (previous) — upgrade tier viable
+  - Confirms gitea 3.5.3+1.24.2-rootless (latest), sqlite3 overlay is right choice for dep
+  - Confirms SCM-configured test must exercise actual OAuth flow (not just /healthz)
+
+### Architecture decisions
+
+**Gitea as dep:**
+- Use `compose.sqlite3.yml` overlay — no mariadb needed for a CI dep; lighter resource footprint
+- `REQUIRE_SIGNIN_VIEW=false` so health check works without login
+- Admin user created via `gitea admin user create` CLI in container post-deploy
+- OAuth2 app created via gitea API (basic auth with ci_admin user)
+
+**SCM-configured test:**
+- Playwright test completes the full gitea→drone OAuth flow
+- Navigates to drone's /login → redirects to gitea OAuth authorize page
+- Fills ci_admin credentials → clicks authorize → lands on drone dashboard
+- Verifies drone `GET /api/user` returns 200 (session valid)
+- This proves the full OAuth circuit works (not just health)
+- Negative teeth: a drone without gitea wiring would not redirect to gitea
+
+**Drone EXTRA_ENV in install_steps.sh:**
+- Sets `COMPOSE_FILE=compose.yml:compose.gitea.yml` (activates gitea SCM overlay)
+- Sets `GITEA_CLIENT_ID`, `GITEA_DOMAIN` from deps creds
+- Creates `client_secret` Docker secret with gitea OAuth2 client_secret
+- Sets `DRONE_USER_CREATE=username:ci_admin,admin:true` (ci_admin = gitea admin user)
+
+**Backup analysis:**
+- Drone recipe compose.yml has `data` volume but NO backupbot labels
+- `abra.sh` only exports `DRONE_ENV_VERSION=v2`, no backup functions
+- Therefore: `backup_capable=False`, backup rung = structural skip (justified in PARITY.md)
+
+### Implementation sequence
+1. Add `setup_gitea_oauth()` to `runner/harness/sso.py`
+2. Update `_enrich_deps_with_sso` in `runner/run_recipe_ci.py` for gitea
+3. Create `tests/gitea/recipe_meta.py`
+4. Create `tests/drone/recipe_meta.py`
+5. Create `tests/drone/install_steps.sh`
+6. Create `tests/drone/functional/test_scm_configured.py`
+7. Create `tests/drone/PARITY.md`
+8. Add unit tests
+
+---
+
+## 2026-06-11 — Implementation
+
+_Evidence of each step logged below as work proceeds._