fix(ci): file-index test and frontend eslint after #160

[EXboys]

Problem / context

PR #160 merged but CI on main still fails:

• Backend: test_workspace_file_index_lists_relative_paths_only expects flat .evotown/ paths; file-index API now lists single-level entries (.evotown directory).
• Frontend: eslint @typescript-eslint/no-explicit-any in CodingAgentWorkspacePage and McpPanel.

Acceptance criteria

• Backend 121 tests pass
• npm run lint reports 0 errors

Refs #159