docs: add upstream PR draft, benchmarks, web client assessment (TODO-057,072,073)

p256 PR draft ready for ReSpeak/tsclientlib submission.
Performance benchmarks document with tsclientlib baselines and
Chanora current metrics. Web client assessed as infeasible without
UDP proxy infrastructure.

docs/references/web-client-feasibility.md

@@ -0,0 +1,68 @@
+# Web Client Feasibility Assessment
+
+**Date:** 2026-06-11
+**Purpose:** Brief assessment of web client feasibility for Chanora (TODO-073)
+
+---
+
+## Precedent: TeaSpeak Web Client
+
+TeaSpeak built a web client (TypeScript, MPL-2.0) that demonstrated:
+- Browser-based TeamSpeak-compatible voice is technically feasible
+- WebAudio API handles Opus decode/encode via WebAssembly
+- Installation-less access is a compelling user benefit
+- VP8 video/screen sharing worked (with bugs)
+
+**Status:** Archived July 2025, unmaintained since ~2022.
+
+---
+
+## Technical Requirements
+
+| Component | Browser API | Feasibility |
+|---|---|---|
+| Audio capture | `getUserMedia()` + `MediaStream` | ✅ Well-supported |
+| Opus encode/decode | WebAssembly (libopus) | ✅ ~100µs encode, feasible |
+| UDP transport | Not available in browsers | ❌ **Blocker** |
+| WebSocket fallback | `WebSocket` | ⚠️ Requires proxy/gateway |
+| TLS/WebRTC | `RTCPeerConnection` | ⚠️ Possible but complex |
+| File transfer | `File` API + WebSocket | ✅ Feasible |
+
+---
+
+## Key Challenge: Transport
+
+TS3 protocol uses **raw UDP** with custom encryption (EAX mode). Browsers cannot send raw UDP packets.
+
+### Options
+
+1. **WebSocket proxy** — Server-side gateway translates WebSocket↔UDP
+   - Requires infrastructure (not self-hosted friendly)
+   - Adds latency (~10-50ms per hop)
+   - Breaks end-to-end encryption
+
+2. **WebRTC data channel** — Browser-to-browser UDP-like channel
+   - Requires signaling server
+   - NAT traversal complexity
+   - Not compatible with TS3 server protocol
+
+3. **WASM + raw sockets** — Not possible (browser sandbox)
+
+---
+
+## Verdict
+
+**Not feasible in current scope.** The UDP transport requirement is a hard blocker without a proxy gateway. Chanora's value proposition (native cross-platform client) conflicts with the infrastructure requirements of a web client.
+
+### If pursued in future
+
+- Build a lightweight WebSocket↔UDP gateway (Rust, ~500 lines)
+- Reuse `chanora_protocol` for server-side translation
+- Host gateway alongside TS3 server or as optional service
+- Web client would be a thin UI layer over the gateway
+
+---
+
+## Recommendation
+
+**Defer indefinitely.** Focus on native client quality. A web client adds significant infrastructure complexity for marginal benefit. TeaSpeak's web client was compelling but ultimately abandoned — the maintenance cost is high relative to native clients.