Add Gitea self-hosted git server

Docker Compose stack (Gitea + Postgres) on port 3000, SSH on 2222,
reverse-proxied via Caddy at git.monotrope.au.

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

infra/ansible/playbook.yml

@@ -10,6 +10,7 @@
     miniflux_db_password: "{{ lookup('env', 'MINIFLUX_DB_PASSWORD') }}"
     miniflux_admin_user: "{{ lookup('env', 'MINIFLUX_ADMIN_USER') | default('admin') }}"
     miniflux_admin_password: "{{ lookup('env', 'MINIFLUX_ADMIN_PASSWORD') }}"
+    gitea_db_password: "{{ lookup('env', 'GITEA_DB_PASSWORD') }}"
     goatcounter_version: "2.7.0"
     goatcounter_admin_email: "{{ lookup('env', 'GOATCOUNTER_ADMIN_EMAIL') }}"
     goatcounter_admin_password: "{{ lookup('env', 'GOATCOUNTER_ADMIN_PASSWORD') }}"
@@ -66,6 +67,7 @@
       notify: Restart Caddy
       tags:
         - miniflux
+        - gitea
         - goatcounter
 
     - name: Enable and start Caddy
@@ -113,6 +115,12 @@
         port: '443'
         proto: tcp
 
+    - name: Allow Gitea SSH
+      ufw:
+        rule: allow
+        port: '2222'
+        proto: tcp
+
     - name: Enable UFW
       ufw:
         state: enabled
@@ -197,6 +205,43 @@
         chdir: /opt/miniflux
       tags: miniflux
 
+    # ── Gitea ───────────────────────────────────────────────────────────────
+
+    - name: Create Gitea directory
+      file:
+        path: /opt/gitea
+        state: directory
+        owner: root
+        group: root
+        mode: '0750'
+      tags: gitea
+
+    - name: Copy Gitea docker-compose.yml
+      copy:
+        src: ../gitea/docker-compose.yml
+        dest: /opt/gitea/docker-compose.yml
+        owner: root
+        group: root
+        mode: '0640'
+      tags: gitea
+
+    - name: Write Gitea .env
+      copy:
+        dest: /opt/gitea/.env
+        owner: root
+        group: root
+        mode: '0600'
+        content: |
+          GITEA_DB_PASSWORD={{ gitea_db_password }}
+      no_log: true
+      tags: gitea
+
+    - name: Pull and start Gitea
+      command: docker compose up -d --pull always
+      args:
+        chdir: /opt/gitea
+      tags: gitea
+
     # ── GoatCounter ─────────────────────────────────────────────────────────
 
     - name: Create goatcounter system user