feat: add n8n_manage_datatable MCP tool with full CRUD (#640) (#650)

* feat: add n8n_create_data_table MCP tool and projectId for create workflow (#640)

Add new MCP tool to create n8n data tables via the REST API:
- n8n_create_data_table tool definition with name + columns schema
- handleCreateDataTable handler with Zod validation and N8nApiError handling
- N8nApiClient.createDataTable() calling POST /data-tables
- DataTable, DataTableColumn, DataTableColumnResponse types per OpenAPI spec
- Column types: string | number | boolean | date | json
- Input validation: .min(1) on table name and column names
- Tool documentation with examples, use cases, and pitfalls

Also adds projectId parameter to n8n_create_workflow for enterprise
project support, and fixes stale management tool count in health check.

Based on work by @djakielski in PR #646.
Co-Authored-By: Dominik Jakielski <dominik.jakielski@urlaubsguru.de>

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* feat: replace n8n_create_data_table with n8n_manage_datatable (10 actions)

Replaces the single-purpose n8n_create_data_table tool with a comprehensive
n8n_manage_datatable tool covering all 10 n8n data table API endpoints:

Table operations: createTable, listTables, getTable, updateTable, deleteTable
Row operations: getRows, insertRows, updateRows, upsertRows, deleteRows

- Filter system with and/or logic and 8 condition operators
- Dry-run support for updateRows, upsertRows, deleteRows
- Pagination, sorting, and full-text search for row listing
- 9 new N8nApiClient methods for all data table endpoints
- Shared error handler and consolidated Zod schemas
- Comprehensive tool documentation with examples per action
- 36 handler tests + 18 API client tests

BREAKING: n8n_create_data_table removed. Use n8n_manage_datatable with
action="createTable" instead.

Based on work by @djakielski in PR #646.
Co-Authored-By: Dominik Jakielski <dominik.jakielski@urlaubsguru.de>

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

tests/unit/mcp/parameter-validation.test.ts

@@ -542,6 +542,9 @@ describe('Parameter Validation', () => {
       await expect(server.testExecuteTool('n8n_test_workflow', {}))
         .rejects.toThrow('Missing required parameters for n8n_test_workflow: workflowId');
 
+      await expect(server.testExecuteTool('n8n_manage_datatable', {}))
+        .rejects.toThrow('n8n_manage_datatable: Validation failed:\n  • action: action is required');
+
       for (const tool of n8nToolsWithRequiredParams) {
         await expect(server.testExecuteTool(tool.name, tool.args))
           .rejects.toThrow(tool.expected);