Rename user-facing UI, page metadata, and docs from the AIML Operations chat
product to Hesychia. Keep live API hosts and deploy webroots; document the
hesychia.ai migration path until infra cutover.
## Summary
- Closes#18
- Replace stale `favicon.jpg` / old ICO with multi-size `favicon.ico`, PNG variants (`16x16`, `32x32`), `logo192.png` / `logo512.png`, and `apple-touch-icon.png` generated from the new brand mark
- Point `index.html` and `manifest.json` at the new assets; drop the CRA placeholder app name in the manifest
## Test plan
- [ ] Hard-refresh the app (or clear site data) and confirm the new logo appears in the browser tab
- [ ] Check DevTools Network for `favicon.ico` / PNG icons — no 404s and no requests for `favicon.jpg`
- [ ] On mobile Safari / iOS home-screen add, confirm apple-touch-icon looks correct
- [ ] Confirm PWA/manifest icons resolve to the new 192/512 assetsReviewed-on: #19