refactor(ui): delete legacy static website and refresh documentation

docs/client/usage.md

@@ -70,7 +70,7 @@ See [LLM](../speech/llm.md), [STT](../speech/stt.md), and [TTS](../speech/tts.md
 |---|---|---|---|
 | `SPEECH_TO_SPEECH_URL` set | Direct to pinned URL | Locked | Disabled |
 | `S2S_PROXY_TARGET` set, no direct URL | Same-origin `/v1/realtime` proxy | Locked | Disabled |
-| `LOAD_BALANCER_URL` set, neither above set | Per-session compute URL from `/api/session` | Hidden | Queue enabled; metering requires `SPACE_ID` too |
+| `LOAD_BALANCER_URL` set, neither above set | Per-session compute URL from `/api/session` | Hidden | Allocation, queue polling and cancellation |
 | None set | User-provided realtime URL | Editable | Disabled |
 
 Direct URLs may be full `ws(s)://.../v1/realtime` addresses or host values that
@@ -84,8 +84,9 @@ server; it is not a universally available local service.
 
 ## Docker
 
-This existing image serves the retained static client. It does not run the
-React/Vite development launcher.
+This image serves FastAPI backend routes and shared documentation. Run the
+React frontend separately with Vite and point `S2S_BACKEND_URL` at the exposed
+backend address. The image does not run the development launcher or serve a UI.
 
 Use the project root as the build context:
 
@@ -144,24 +145,22 @@ The warmup is a timer, not proof that all upstream context requests have
 finished. Browser permission and audio policies can still require a gesture.
 The greeting uses the same `hola vocero` input as wake-word handling.
 
-## Queue and daily usage
+## Queue and session lifecycle
 
-Load-balancer mode proxies session acquisition and queue polling. Waiting does
-not reserve conversation time; a daily budget is reserved when a compute slot
-is granted. The server enables metering only with both `LOAD_BALANCER_URL` and
-`SPACE_ID` and with neither pinned direct/proxy mode active.
+Load-balancer mode proxies `POST /api/session`. A free compute slot returns a
+grant containing `session_id`, `connect_url`, and `pending_timeout_s`. Otherwise
+the browser receives a queue ticket and polls `GET /api/queue/{queue_id}` until
+a slot is granted. The browser offers a timed join action after waiting.
 
-| Environment setting | Default | Purpose |
-|---|---|---|
-| `LIMIT_ANON_SEC` | 300 | Anonymous seconds per UTC day |
-| `LIMIT_FREE_SEC` | 600 | Signed-in non-PRO seconds per UTC day |
-| `UNLIMITED_ORGS` | Adds to built-in organizations | Additional unlimited organization members |
-| `USAGE_HASH_SECRET` | Random if unset | Identity-key hashing and anonymous cookie signing |
+`DELETE /api/queue/{queue_id}` cancels a waiting ticket. On session stop or page
+exit, the browser uses `POST /api/queue/end` through `sendBeacon`, falling back
+to a keepalive fetch. Expired tickets and missed join deadlines require a new
+attempt. Full queues return `503` with `state: "at_capacity"`.
 
-PRO members are unlimited. Built-in unlimited organizations are `cerebras`,
-`HuggingFaceM4`, `smolagents`, and `pollen-robotics`; organization matching is
-case-insensitive. See [auth.py](../../s2s-client/auth.py) and
-[limiter.py](../../s2s-client/limiter.py) for the current enforcement behavior.
+Once connected, session teardown closes the microphone, audio graph and
+WebSocket. The 30-second inactivity timeout remains active when the assistant
+is not speaking. Caller-profile lookup and upstream authorization operate
+independently of allocation and use their existing configured endpoints.
 
 For external transcript processing, configure the selected
 [reasoning mode](reasoning.md). For connection, context and audio diagnostics,