[codex] Add MC0 BLE companion transport

.github/workflows/firmware.yml

@@ -45,7 +45,7 @@ jobs:
 
       - name: Run Python tooling selftests
         run: |
-          python -m py_compile scripts/check_tdeck_budget.py scripts/fetch_tdeck_artifact.py scripts/serial_harness.py scripts/tdeck_smoke.py scripts/tdm_airtime_smoke.py
+          python -m py_compile scripts/check_tdeck_budget.py scripts/fetch_tdeck_artifact.py scripts/serial_harness.py scripts/tdeck_smoke.py scripts/tdm_airtime_smoke.py scripts/mc_companion_usb_smoke.py scripts/mc_companion_ble_smoke.py
           python scripts/tdm_airtime_smoke.py --selftest
       - name: Validate local app samples
         run: |

README.md

@@ -128,11 +128,14 @@ iPhone-style dark look (status bar, battery glyph, grouped settings cards).
   enabling one frees the other.
 
 ### 🔭 Later
-- **MeshCore companion bridge** — V0 protocol foundation is drafted, and an
-  initial `companion mc ...` USB serial-console smoke surface can report
-  snapshots and exercise send boundaries; the formal USB/BLE bridge remains
-  planned, and it is not official MeshCore app compatible unless the real
-  MeshCore app protocol is confirmed.
+- **MeshCore companion bridge** — V0 USB foundation is in progress:
+  `companion mc ...` covers console smoke, and `companion mc usb on` enters
+  formal MC0 mode for identity/status/node/thread snapshots, send boundaries,
+  revision counters, event controls, and bounded node/message/TX event draining.
+  Private MC0-over-BLE transport is available for LimitlezzOS/test clients via
+  `companion mc ble on` and the custom `Limitlezz-MC0-*` GATT service. It is not
+  official MeshCore app compatible unless the real MeshCore app protocol is
+  confirmed and mapped.
 - **Roll the iPhone look everywhere** — grouped cards / dividers across Messages, Nodes, Contacts.
 - **Local app platform** - scan local app manifests from `/sd/limitlezz/apps`,
   `/sd/apps`, `/appfs/apps`, and simulator data dirs, then show accepted apps
@@ -185,7 +188,7 @@ iPhone-style dark look (status bar, battery glyph, grouped settings cards).
 - [`docs/tdeck-firmware-audit.md`](docs/tdeck-firmware-audit.md) - current firmware audit and risk list.
 - [`docs/tdeck-feature-inventory.md`](docs/tdeck-feature-inventory.md) - feature-by-feature implementation inventory.
 - [`docs/tdeck-firmware-roadmap.md`](docs/tdeck-firmware-roadmap.md) - roadmap to a complete T-Deck firmware.
-- [`docs/tdeck-meshcore-companion-protocol.md`](docs/tdeck-meshcore-companion-protocol.md) - draft Phase 5/V0.8 MeshCore companion line protocol.
+- [`docs/tdeck-meshcore-companion-protocol.md`](docs/tdeck-meshcore-companion-protocol.md) - Phase 5/V0.8 MeshCore companion V0 protocol.
 - [`docs/tdeck-hardware-dogfood-checklist.md`](docs/tdeck-hardware-dogfood-checklist.md) - stock-device hardware proof checklist.
 - [`docs/tdeck-release-checklist.md`](docs/tdeck-release-checklist.md) - slow-host Actions artifact and COM8 release evidence checklist.
 - [`docs/tdeck-troubleshooting.md`](docs/tdeck-troubleshooting.md) - build, flash, boot, radio, storage, Wi-Fi, and companion troubleshooting.

docs/tdeck-feature-inventory.md

@@ -75,7 +75,7 @@ Status labels:
 | MeshCore self-advert TX | Partial, needs validation | Ed25519 identity, self-advert builder, serial/UI advert commands | Needs interop proof with real MeshCore nodes. |
 | MeshCore public channel / rooms | Planned | README says receive/default Public channel still ahead | V0.6: implement group text decode/send, room model, and split airtime config. |
 | MeshCore DMs | Planned | MeshCore contacts are non-messageable while gated | V0.7: implement key/session model, send path, ACKs, and UI routing. |
-| MeshCore companion bridge | Planned/In progress | `docs/tdeck-meshcore-companion-protocol.md` drafts the V0 USB serial line protocol; `companion mc ...` provides an initial firmware smoke surface for snapshots, sends, and self-test | V0.8: formalize USB first, mirror to BLE later, and do not claim external MeshCore app compatibility until the real app protocol is confirmed. |
+| MeshCore companion bridge | Partial/In progress | `docs/tdeck-meshcore-companion-protocol.md` defines the V0 MC0 line protocol; `companion mc ...` provides console smoke coverage, `companion mc usb on` enters formal USB MC0 mode for identity/status/node/thread snapshots, send boundaries, event controls, revision counters, and bounded node/message/TX event drain, and `companion mc ble on` advertises a private `Limitlezz-MC0-*` GATT service for the same logical protocol | V0.8: hardware-validate USB and BLE MC0 with TX-event smoke, add BLE client/reconnect soak, and do not claim external MeshCore app compatibility until the real app protocol is confirmed. |
 
 ## User Interface
 

docs/tdeck-firmware-roadmap.md

@@ -47,7 +47,7 @@ These maintainer-provided beta labels are the canonical near-term sequence. The
 | V0.6 | MeshCore public chat and split airtime config | 🚧 Public chat send/receive hardware-verified; **split airtime may not be working — needs re-verification**; config UI still TODO |
 | V0.6 | MeshCore public chat and split airtime config | In progress - public chat send/receive hardware-verified; split-airtime serial dwell/switch smoke passed on COM8; packet-loss, latency, and real dual-network traffic soak still open |
 | V0.7 | MeshCore DMs and private chats | ✅ Encrypted DMs (X25519 ECDH + AES) send/receive hardware-verified against a real MeshCore peer |
-| V0.8 | MeshCore USB companion and MeshCore BLE companion | 🚧 Protocol foundation drafted; USB/BLE implementation still planned and not external-app compatible yet |
+| V0.8 | MeshCore USB companion and MeshCore BLE companion | In progress - USB MC0 mode covers identity/status/node/thread snapshots, send boundaries, revision counters, event controls, and COM8 smoke hooks; private MC0-over-BLE service is implemented for LimitlezzOS/test clients; official MeshCore app compatibility remains unclaimed |
 | V0.9 | Code review, optimization, and emoji polish | ⬜ Not started |
 | V0.95 | Basic app SDK and infrastructure; Home UI supports adding apps and multiple home screens | 🚧 Local manifest scanner, Home paging, and detail shell started; runtime/catalog still TODO |
 | V0.96 | Upgraded Wi-Fi password storage | ✅ Implemented on T-Deck hardware: credentials use ESP32 NVS, legacy `wifi.cfg` migrates/removes, and diagnostics do not print passwords |
@@ -189,18 +189,27 @@ Exit criteria:
 
 Goal: expose MeshCore companion functionality only after native MeshCore messaging is stable.
 
-**Status:** protocol foundation in progress with an initial USB serial-console
-smoke surface. `companion mc hello|status|nodes|threads|send|dm|test` now
-exercises the firmware-owned MeshCore snapshots and send boundaries for COM8
-validation, while the formal `MC0` bridge, BLE transport, events, and real
-external MeshCore app compatibility are still planned work.
+**Status:** USB-first protocol foundation in progress. `companion mc
+hello|status|nodes|threads|send|dm|test` still exercises the firmware-owned
+MeshCore snapshots and send boundaries for COM8 validation, and formal
+`companion mc usb on` MC0 mode now handles `HELLO`, `IDENTITY`, `STATUS`,
+`NODES`, `THREADS`, `SEND_PUBLIC`, `SEND_DM`, `EVENTS`, and `EXIT` with
+snapshot revisions plus bounded node/message/TX event draining. Private
+MC0-over-BLE mode exposes the same line protocol through a LimitlezzOS-specific
+GATT service for test clients; real external MeshCore app compatibility remains
+planned work until the app protocol is confirmed and mapped.
 
 Deliverables:
 
 - Define the MeshCore companion protocol surface for node DB, public chat, private chats, and send/receive forwarding. Drafted as `docs/tdeck-meshcore-companion-protocol.md`.
 - Add a USB serial-console smoke surface that reports MeshCore companion status, nodes, threads, Public send, DM send, and self-test.
-- Implement MeshCore USB companion mode.
-- Implement MeshCore BLE companion mode.
+- Implement MeshCore USB companion mode. In progress: MC0 USB request/response
+  mode is implemented for identity, status, node/thread snapshots, send
+  boundaries, exact full-public-key DM routing, event controls, bounded event
+  draining, and reconnect/resync counters.
+- Implement MeshCore BLE companion mode. In progress: private MC0 BLE service
+  mirrors the USB logical protocol over custom RX/TX GATT characteristics; BLE
+  client hardware smoke and external protocol mapping remain.
 - Add UI and serial commands that distinguish Meshtastic companion from MeshCore companion.
 - Decide whether one companion session or one network can own the external-app bridge at a time.
 - Confirm the real MeshCore app protocol before claiming compatibility with existing external MeshCore apps.