docs: update README, AGENTS.md, Makefile, and architecture docs

docs/ARCHITECTURE.md

@@ -5,7 +5,7 @@
 `webterm` is a Go HTTP/WebSocket server that hosts one or more terminal sessions and renders screenshot/telemetry surfaces for a dashboard UI.
 
 ```
-Browser (terminal.js + ghostty-vt.wasm)
+Browser (generated terminal.js + ghostty-vt.wasm)
         │
         │ WS / HTTP / SSE
         ▼
@@ -42,7 +42,7 @@ webterm/server.go (LocalServer)
 Assets live in `webterm/static`:
 
 - `js/terminal.ts` source
-- `js/terminal.js` bundled client
+- `js/terminal.js` generated bundled client
 - `js/ghostty-vt.wasm`
 - `monospace.css`, icons, `manifest.json`