Add Test Connection to OpenAPI, Azure Maps, Blob Storage, Databricks, Log Analytics, MCP, Snowflake, and Tableau actions #1267

Summary

Only the SQL and Cosmos action types expose a Test Connection button in the action (plugin) modal. Add the same capability to eight more action types:

openapi, azure_maps_openlayers, blob_storage, databricks, log_analytics, mcp, snowflake, tableau.

User Value

Today, a bad Databricks warehouse ID, Blob container name, Azure Maps subscription key, Tableau PAT, Snowflake account, Log Analytics workspace ID, MCP endpoint, or OpenAPI base URL is only discovered when an agent actually invokes the tool at chat time. Admins and workspace owners have to save, run a chat, read a failure, and guess. A pre-save Test Connection turns that into an immediate, actionable message in the modal — the same experience SQL and Cosmos actions already have.

Proposed Behavior

Follow the existing SQL/Cosmos pattern.

Backend

• New shared module application/single_app/functions_action_connection_tests.py with one tester per action type. Routes stay thin.
• Eight dedicated routes on the bpap blueprint, matching the existing /api/plugins/test-sql-connection naming:
  • POST /api/plugins/test-openapi-connection
  • POST /api/plugins/test-azure-maps-connection
  • POST /api/plugins/test-blob-storage-connection
  • POST /api/plugins/test-databricks-connection
  • POST /api/plugins/test-log-analytics-connection
  • POST /api/plugins/test-mcp-connection
  • POST /api/plugins/test-snowflake-connection
  • POST /api/plugins/test-tableau-connection
• A shared _prepare_action_test_manifest(...) helper in route_backend_plugins.py that reuses the existing _load_existing_plugin_for_test, _resolve_action_identity_context, ui_trigger_word re-hydration, hydrate_action_identity_reference, _resolve_secret_value_for_plugin_test, and PluginHealthChecker.validate_plugin_manifest flow, so masked secrets and reusable identities keep working on edit.

What each test verifies (full verification: authenticate, then one lightweight read)

Frontend

• Test Connection button plus a result alert in each of the eight Step 3 config sections in templates/_plugin_modal.html.
• One shared JS runner in static/js/plugin_modal_stepper.js so loading/success/error UX is identical across all eight.
• Log Analytics currently has no dedicated Step 3 section (it uses the generic endpoint/auth form, with Workspace ID and Cloud rendered dynamically in Step 4 → Advanced → Additional Fields). Give it a dedicated Step 3 section with Workspace ID, Cloud, Authority Host / Endpoint Override, endpoint, and its own auth block, so the Test Connection button sits next to the config it validates.

Acceptance Criteria

• All eight action types show a working Test Connection button in the action modal, for personal, group, and admin/global scopes
• Each test authenticates and performs one lightweight read against the configured resource, and reports a specific, actionable message
• Auth failures, not-found resources, and transport errors are distinguishable in the returned message
• Existing actions can be tested in edit mode without re-entering masked (ui_trigger_word) secrets, and reusable workspace identities are hydrated before the test runs
• No credential value is ever echoed back to the browser; all exception text is sanitized
• The MCP test route enforces the same stdio scope restriction and outbound destination policy as /api/plugins/mcp/discover, so it does not become a weaker SSRF path
• Missing optional packages (snowflake-connector-python, tableauserverclient, azure-monitor-query) return a clear message rather than a 500
• Log Analytics gets a dedicated Step 3 section, and existing log_analytics actions keep their manifest shape, including query_history and any other stored additionalFields keys
• Every new route carries @swagger_route(security=get_auth_security()) plus @login_required and @user_required
• Functional tests cover route registration and decorators, secret redaction, and Log Analytics config round-tripping
• Playwright UI tests cover the button and mocked success/failure alerts for all eight types
• docs/explanation/features/ACTION_TEST_CONNECTION.md added and config.py VERSION bumped

Notes

• The existing /api/plugins/test-sql-connection and /api/plugins/test-cosmos-connection routes are left untouched.
• Testers reuse the existing plugin classes and factories (OpenApiPluginFactory, BlobStoragePlugin, DatabricksPluginFactory, LogAnalyticsPlugin, McpPluginFactory, SnowflakePluginFactory, TableauPluginFactory) rather than reimplementing clients.
• No files under deployers/ change, so deployers/version.txt is not bumped.
• Suggested size: L (backend module, eight routes, template and JS changes, plus functional and UI test coverage).