feat(astrolabe): add dynamic MCP server configuration for testing

Replace static post-installation configuration with dynamic test-time
configuration to support testing multiple MCP server deployments.

Changes:
- Remove static MCP server URL and OAuth client setup from post-installation
- Add configure_astrolabe_for_mcp_server fixture (session-scoped)
- Fixture dynamically configures:
  * Nextcloud system config (mcp_server_url, mcp_server_public_url)
  * OAuth client creation via occ oidc:create
  * Client credential storage (astrolabe_client_id, astrolabe_client_secret)
- Update existing OAuth tests to use dynamic configuration
- Add test_astrolabe_multi_server_integration.py with parametrized tests

Benefits:
- Test Astrolabe with mcp-oauth, mcp-keycloak, mcp-multi-user-basic
- Each test configures for its specific MCP server
- No static configuration conflicts between deployments
- Cleaner post-installation (37 lines, down from 85)

Test Results:
- test_astrolabe_configuration_for_different_servers: PASSED (mcp-oauth, mcp-keycloak)
- test_astrolabe_reconfiguration: PASSED

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

app-hooks/post-installation/20-install-astrolabe-app.sh

@@ -2,7 +2,7 @@
 
 set -euox pipefail
 
-echo "Installing and configuring Astrolabe app for testing..."
+echo "Installing Astrolabe app for testing..."
 
 # Check if development astrolabe app is mounted at /opt/apps/astrolabe
 if [ -d /opt/apps/astrolabe ]; then
@@ -30,55 +30,7 @@ else
     php /var/www/html/occ app:enable astrolabe
 fi
 
-# Configure MCP server URLs in Nextcloud system config
-# - mcp_server_url: Internal URL for PHP app to call MCP server APIs (Docker internal network)
-# - mcp_server_public_url: Public URL for OAuth token audience (what browsers/MCP clients see)
-php /var/www/html/occ config:system:set mcp_server_url --value='http://mcp-oauth:8001'
-php /var/www/html/occ config:system:set mcp_server_public_url --value='http://localhost:8001'
-
-# Create OAuth client for Astrolabe app
-# The resource_url MUST match what the MCP server expects as token audience
-# This allows tokens from this client to be validated by MCP server's UnifiedTokenVerifier
-MCP_CLIENT_ID="nextcloudMcpServerUIPublicClient"
-MCP_RESOURCE_URL="http://localhost:8001"
-MCP_REDIRECT_URI="http://localhost:8080/apps/astrolabe/oauth/callback"
-
-echo "Configuring OAuth client for Astrolabe..."
-
-# Check if client already exists
-if php /var/www/html/occ oidc:list 2>/dev/null | grep -q "$MCP_CLIENT_ID"; then
-    echo "OAuth client $MCP_CLIENT_ID already exists, removing to recreate with correct settings..."
-    php /var/www/html/occ oidc:remove "$MCP_CLIENT_ID" || true
-fi
-
-# Create OAuth client with correct resource_url for MCP server audience
-echo "Creating OAuth confidential client with resource_url=$MCP_RESOURCE_URL"
-CLIENT_OUTPUT=$(php /var/www/html/occ oidc:create \
-    "Astrolabe" \
-    "$MCP_REDIRECT_URI" \
-    --client_id="$MCP_CLIENT_ID" \
-    --type=confidential \
-    --flow=code \
-    --token_type=jwt \
-    --resource_url="$MCP_RESOURCE_URL" \
-    --allowed_scopes="openid profile email offline_access notes:read notes:write calendar:read calendar:write contacts:read contacts:write cookbook:read cookbook:write deck:read deck:write tables:read tables:write files:read files:write")
-
-echo "$CLIENT_OUTPUT"
-
-# Extract client_secret from JSON output
-CLIENT_SECRET=$(echo "$CLIENT_OUTPUT" | php -r 'echo json_decode(file_get_contents("php://stdin"), true)["client_secret"] ?? "";')
-
-if [ -n "$CLIENT_SECRET" ]; then
-    echo "Configuring Astrolabe client secret in system config..."
-    php /var/www/html/occ config:system:set astrolabe_client_secret --value="$CLIENT_SECRET"
-    echo "✓ Client secret configured: ${CLIENT_SECRET:0:8}..."
-else
-    echo "⚠ Warning: Could not extract client_secret from OIDC client creation"
-fi
-
-# Configure OAuth client ID in system config
-echo "Configuring Astrolabe client ID in system config..."
-php /var/www/html/occ config:system:set astrolabe_client_id --value="$MCP_CLIENT_ID"
-echo "✓ Client ID configured: $MCP_CLIENT_ID"
-
-echo "Astrolabe app installed and configured successfully"
+echo "✓ Astrolabe app installed successfully"
+echo ""
+echo "Note: MCP server configuration is managed dynamically during tests"
+echo "      to support testing multiple MCP server deployments."