Plugin / extension system (stretch goal)

[kafkade]

Tracks Phase 5.6 — Plugin / Extension System (Stretch Goal) from docs/SPEC.md §5.

Goal

Let users extend Kite with custom collectors, panels, metrics, and alert actions without forking.

Scope

• Plugin API — Lua or WASM based, for custom collectors
• Plugins can add new panels, metrics, and alert actions
• Plugin repository / registry for discovery and install
• Example plugins: Postgres stats, Redis info, custom application metrics

Notes

• Stretch goal — lowest priority in Phase 5; design should not compromise the "single static binary, no runtime deps" constraint (SPEC §6) for the core app.
• Plugins integrate at the Collector trait boundary (src/collector/) and the widget layer (src/ui/widgets/).