v0.2.1 — coverage expansion

Four ecosystems added, prompted by launch-day feedback:

• Kilo CLI — agent detection plus full MCP-server parsing from
  ~/.config/kilo/kilo.jsonc (JSONC comments handled) and project-level
  .kilo/kilo.jsonc / kilo.jsonc.
• Grok Build (xAI) — ~/.grok home with config.toml scanned for
  secret shapes and MCP declarations.
• Firefox — AI extensions per profile from extensions.json, with
  granted permissions mapped the same way as Chromium browsers
  (broad origins → BROAD-WEB, nativeMessaging → EXECUTES).
• JetBrains — AI Assistant / MCP settings detection per IDE product.
  JetBrains stores MCP config inside the IDE settings store rather than a
  documented file, so geiger reports that it exists, where, and which
  settings screen to review (medium confidence, honestly labeled). The
  Junie agent's ~/.junie home is detected alongside the other agent CLIs.

No behavior changes to existing detectors. Read-only, no telemetry, secrets
by shape only — unchanged, as always.