feat(doctor): add Antigravity and Gemini CLI config paths

Add ~/.gemini/settings.json (Gemini CLI) and
~/.gemini/antigravity/mcp_config.json (Antigravity) to the
default MCP config scan list.

src/doctor.ts

@@ -83,6 +83,8 @@ export function getDefaultMcpConfigPaths(cwd: string = process.cwd()): string[]
     path.join(home, '.codex', 'mcp.json'),
     path.join(home, '.cursor', 'mcp.json'),
     path.join(home, '.claude.json'),
+    path.join(home, '.gemini', 'settings.json'),
+    path.join(home, '.gemini', 'antigravity', 'mcp_config.json'),
     path.join(home, '.config', 'opencode', 'opencode.json'),
     path.join(home, 'Library', 'Application Support', 'Claude', 'claude_desktop_config.json'),
     path.join(home, '.config', 'Claude', 'claude_desktop_config.json'),