v0.0.28 - Finalize Feather TinyUSB migration and remove cardputer artifacts

README.md

@@ -248,11 +248,14 @@ Discovery:
 - `nsigner --listen qrexec` is the same stdio framing mode, but caller identity can be derived from `QREXEC_REMOTE_DOMAIN` (displayed as `qubes:<source-vm>`).
 - `nsigner --listen tcp:IPv4:PORT` or `tcp:[IPv6]:PORT` enables TCP listening for non-AF_UNIX clients (for example `tcp:127.0.0.1:8080`, `tcp:[::]:8080`, or `tcp:[fd00::1234]:8080`).
 
-### 7.2 ESP32 MCU: USB-CDC serial
+### 7.2 ESP32 MCU: TinyUSB composite (CDC + WebUSB)
 
-On MCU targets, the same core modules run with a different transport adapter: USB-CDC serial framing instead of AF_UNIX.
+On Feather S3 TFT, MCU targets run the same core signer modules behind a TinyUSB composite transport:
 
-Core logic stays the same; only transport/UI bindings change.
+- CDC-ACM framed JSON-RPC for serial tooling (`/dev/ttyACM*`)
+- Vendor/WebUSB framed JSON-RPC for browser tooling
+
+Core signer logic stays the same; only transport/UI bindings change.
 
 ### 7.3 NIP-46 relay flow (both platforms)
 
@@ -276,7 +279,7 @@ Primary deployment is a local, foreground terminal program with abstract namespa
 
 ### 8.2 ESP32 / MCU
 
-MCU target reuses mnemonic/role/selector/enforcement/dispatcher core and swaps transport/UI for constrained hardware (for example UART/OLED/buttons or USB-CDC host interaction).
+MCU target reuses mnemonic/role/selector/enforcement/dispatcher core and swaps transport/UI for constrained hardware. The Feather path currently uses TinyUSB composite USB (CDC + WebUSB) plus TFT/buttons for attended approvals.
 
 ### 8.3 Qubes OS qube
 
@@ -391,7 +394,21 @@ Static build:
 ./build/nsigner_static_x86_64 --version
 ```
 
-## 11. Document map
+## 11. Implemented adjuncts and future work
+
+### Implemented PoC
+
+- **MCU / USB signer (Feather ESP32-S3 Reverse TFT).** Working PoC in [`firmware/feather_s3_tft`](firmware/feather_s3_tft). Single TinyUSB composite USB device exposes both CDC-ACM and WebUSB Vendor interfaces. Same dispatcher serves both transports with auth envelope verification, on-device TFT prompts, and physical button approval. See [`firmware/README.md`](firmware/README.md) and [`plans/feather_tinyusb_composite.md`](plans/feather_tinyusb_composite.md).
+
+### Future work (deferred)
+
+These items are designed and worth doing, but are not in the current implementation scope. They are listed here so they are not lost.
+
+- **`--listen http:[addr]:port` mode.** Today the TCP listener speaks 4-byte big-endian length-prefixed framed JSON-RPC, which is correct for low-overhead local IPC but is not directly reachable from web browsers (`fetch`, `XMLHttpRequest`, `curl`). A small additional listener that wraps the same dispatcher in minimal HTTP/1.1 (`POST /rpc`, `Content-Type: application/json`, `Content-Length`-framed body, JSON response) would let standard HTTP clients talk to `nsigner` without any custom framing code. The existing auth envelope (`kind:27235`) and JSON-RPC contract are unchanged; only the outer framing differs. CORS allow on the response would let browser extensions and (with TLS) HTTPS pages reach a remote `nsigner` over FIPS or any other carrier. See the discussion in [`documents/FIPS_DEPLOYMENT.md`](documents/FIPS_DEPLOYMENT.md) section 9 ("Next hardening steps").
+- **NIP-46 bunker / relay transport.** Tracked in [`plans/nip46_bunker_mode.md`](plans/nip46_bunker_mode.md).
+- **Browser extension.** Tracked in [`plans/nsigner_browser_extension.md`](plans/nsigner_browser_extension.md). NIP-07 surface forwarding to a running `nsigner` instance.
+
+## 12. Document map
 
 - [`README.md`](README.md): authoritative behavior specification for the foreground single-program model
 - [`documents/CLIENT_IMPLEMENTATION.md`](documents/CLIENT_IMPLEMENTATION.md): client integration contract and framing behavior
@@ -399,4 +416,8 @@ Static build:
 - [`documents/FIPS_DEPLOYMENT.md`](documents/FIPS_DEPLOYMENT.md): Tier-1 FIPS deployment runbook using loopback TCP listener
 - [`plans/nsigner.md`](plans/nsigner.md): implementation plan and sequencing
 - [`plans/seed_phrase_uses.md`](plans/seed_phrase_uses.md): seed phrase domain/use catalog and caveats
+- [`firmware/feather_s3_tft`](firmware/feather_s3_tft): Feather ESP32-S3 Reverse TFT firmware (TinyUSB composite CDC + WebUSB signer PoC)
+- [`plans/feather_tinyusb_composite.md`](plans/feather_tinyusb_composite.md): firmware Phase 7b plan and outcome (TinyUSB composite USB transport)
+- [`plans/nsigner_browser_extension.md`](plans/nsigner_browser_extension.md): browser extension exposing NIP-07 over `nsigner`
+- [`plans/nip46_bunker_mode.md`](plans/nip46_bunker_mode.md): deferred NIP-46 relay-mode signer transport
 - [`firmware/README.md`](firmware/README.md): firmware-side notes for MCU transport/UI integration