feat: add Docker Compose profiles and Login Flow v2 service

Add selective service startup via Docker Compose profiles so each MCP
deployment mode runs independently. Also add the new mcp-login-flow
service (port 8004) for Login Flow v2 authentication (ADR-022).

Profile assignments:
- single-user: mcp (port 8000)
- multi-user-basic: mcp-multi-user-basic (port 8003)
- oauth: mcp-oauth (port 8001)
- keycloak: keycloak + mcp-keycloak (port 8002)
- login-flow: mcp-login-flow (port 8004)

Infrastructure services (db, redis, app, recipes) always start.

Integration tests cover the full Login Flow v2 provisioning flow:
OAuth → browser login → app password → Nextcloud API access for
notes, calendar, contacts, files, deck, and cookbook operations.

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

pyproject.toml

@@ -64,7 +64,7 @@ Changelog = "https://github.com/cbcoutinho/nextcloud-mcp-server/blob/master/CHAN
 
 [tool.pytest.ini_options]
 anyio_mode = "auto"
-addopts = "-p no:asyncio"  # Disable pytest-asyncio plugin, use only anyio
+addopts = "--headed -p no:asyncio"  # Disable pytest-asyncio plugin, use only anyio
 log_cli = 1
 log_cli_level = "ERROR"
 log_level = "ERROR"
@@ -74,6 +74,7 @@ markers = [
     "oauth: OAuth tests requiring Playwright (slowest)",
     "smoke: Critical path smoke tests for quick validation",
     "keycloak: OAuth tests that utilize keycloak external identity provider",
+    "login_flow: Login Flow v2 integration tests (ADR-022)",
 ]
 testpaths = [
     "tests",