docs: rewrite README with structured overview and quick start guide

Replaces the minimal project description with a comprehensive README
including a component overview table, quick start instructions, common
Ansible operations, and links to detailed documentation. Aligns with
Red Panda Approval™ standards.

ansible/gitea_mcp/docker-compose.yml.j2

@@ -0,0 +1,18 @@
+services:
+  gitea-mcp:
+    image: docker.gitea.com/gitea-mcp-server:latest
+    pull_policy: always
+    container_name: gitea-mcp
+    restart: unless-stopped
+    ports:
+      - "{{gitea_mcp_port}}:8000"
+    environment:
+      - GITEA_HOST={{gitea_mcp_host}}
+      - GITEA_ACCESS_TOKEN={{gitea_mcp_access_token}}
+    command: ["/app/gitea-mcp", "-t", "http", "--port", "8000"]
+    logging:
+      driver: syslog
+      options:
+        syslog-address: "tcp://127.0.0.1:{{gitea_mcp_syslog_port}}"
+        syslog-format: "{{syslog_format}}"
+        tag: "gitea-mcp"