test(studio-mcp): add comprehensive tests for all new MCP tools

68 new tests across 3 test files:

- run-detail-tools.spec.ts (23 tests): get_run_config, get_run_trace,
  list_run_node_io, get_node_io (with ensureRunAccess security check),
  get_run_logs, list_child_runs, permission gating
- artifact-tools.spec.ts (24 tests): list_artifacts, list_run_artifacts,
  view_artifact (text windowing, binary detection, offset/limit, hasMore),
  unavailable service fallback, permission gating
- domain-tools.spec.ts (21 tests): schedule CRUD (inputPayload mapping),
  secret CRUD, human-input resolve (DTO shape, status override prevention),
  permission gating for all domains

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Signed-off-by: betterclever <paliwal.pranjal83@gmail.com>

Author: betterclever