docs: clarify multi-set and CDN-loaded object icons

docs/implementation-plan.md

@@ -212,11 +212,13 @@ proxy API and `packages/extract` directly for analysis.
 - `components/viewers.tsx` — viewer registry (`registerViewer` /
   `resolveViewer`) plus a `DefaultViewer` that renders an object's fields;
   custom per-class viewers can be registered later.
-- `components/objectIcons.tsx` — maps TTS object classes to one or more MDI
-  icons (`iconsForObject`); unknown classes fall back to a help icon.
+- `components/objectIcons.tsx` — maps TTS object classes to one or more
+  Iconify icons (`iconsForObject`); unknown classes fall back to a help icon.
+  Icons may come from multiple sets (mdi, material-symbols, file-icons, ...);
+  names not bundled are fetched from the Iconify CDN at runtime.
 - `components/objectIconsData.ts` — generated by
-  `scripts/generate-object-icons.mjs`; registers only the used MDI icons with
-  Iconify's offline storage so the full set isn't bundled.
+  `scripts/generate-object-icons.mjs`; registers a small mdi subset with
+  Iconify's offline storage so those render without a network round-trip.
 - `stores/searchStore.ts` / `stores/modStore.ts` — Zustand stores for search
   and mod state.
 - `vite.config.ts` — dev proxy for `/search`, `/items`, `/health` →