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+# ADR-110 — Branch state (as of 2026-05-23, iter 22)
+
+Reference card for anyone collaborating on or near the ADR-110 work. The /loop SOTA sprint that closed the firmware-side substrate ran into multiple cross-branch checkout incidents (see iter 17-19); this page exists so the next collaborator doesn't have to re-derive the layout from `git log`.
+
+## Branch ownership
+
+| Branch | Owner | What it carries | Don't merge from |
+|---|---|---|---|
+| `main` | shared | shipped release line | — |
+| `adr-110-esp32c6` | ADR-110 / C6 firmware substrate | Everything described in `WITNESS-LOG-110 §A0.x` (4 firmware tags v0.6.7 → v0.7.0, Python + Rust decoders, sensing-server wire, mesh-aligned timestamp recovery, fps EMA, cross-language conformance gate) | Don't accidentally land `feat/adr-115-ha-mqtt-matter` work here uncommitted |
+| `feat/adr-115-ha-mqtt-matter` | ADR-115 / HA-DISCO + HA-FABRIC + HA-MIND | MQTT publisher (`rumqttc`), Matter Bridge, semantic automation primitives, related Cargo features + CLI flags | Don't accidentally land ADR-110 `wifi-densepose-hardware` dep mods here |
+
+## Files each branch touches
+
+### `adr-110-esp32c6` — primary modifications
+
+```
+firmware/esp32-csi-node/version.txt                              # bumped 0.6.6 → 0.7.0
+firmware/esp32-csi-node/main/c6_*.{c,h}                          # LP-core, TWT, timesync, soft-AP HE, ESP-NOW sync
+firmware/esp32-csi-node/main/lp_core/main.c                      # real LP-core polling program
+firmware/esp32-csi-node/main/csi_collector.c                     # byte 19 bit 4 OR-fix; sync packet emit
+firmware/esp32-csi-node/main/Kconfig.projbuild                   # C6_* knobs
+firmware/esp32-csi-node/main/CMakeLists.txt                      # ulp_embed_binary
+firmware/esp32-csi-node/sdkconfig.defaults.esp32c6               # C6 overlay
+
+archive/v1/src/hardware/csi_extractor.py                         # SyncPacketParser + SyncPacket dataclass
+archive/v1/tests/unit/test_esp32_binary_parser.py                # TestSyncPacketParser (7 tests)
+
+v2/crates/wifi-densepose-hardware/src/sync_packet.rs             # new module (15 tests)
+v2/crates/wifi-densepose-hardware/src/lib.rs                     # re-exports
+v2/crates/wifi-densepose-sensing-server/Cargo.toml               # ONLY adds wifi-densepose-hardware path dep
+v2/crates/wifi-densepose-sensing-server/src/main.rs              # NodeState::{latest_sync, csi_fps_ema,
+                                                                 #            mesh_aligned_us_for_csi_frame,
+                                                                 #            observe_csi_frame_arrival}
+                                                                 # udp_receiver_task magic dispatch
+                                                                 # fps_ema_tests module (4 tests)
+
+docs/adr/ADR-110-esp32-c6-firmware-extension.md                  # 670 → ~750 lines (P10 + sprint summary)
+docs/WITNESS-LOG-110.md                                          # 13 §A0.x entries
+docs/ADR-110-REVIEW-GUIDE.md                                     # reviewer one-pager
+docs/ADR-110-BRANCH-STATE.md                                     # ← this file
+```
+
+### `feat/adr-115-ha-mqtt-matter` — primary modifications
+
+```
+docs/adr/ADR-115-home-assistant-integration.md                   # the design
+v2/crates/wifi-densepose-sensing-server/Cargo.toml               # rumqttc dep + [features] block
+v2/crates/wifi-densepose-sensing-server/src/cli.rs               # --mqtt / --matter / --semantic flags
+```
+
+## Known overlap points (handle with care)
+
+Both branches touch `v2/crates/wifi-densepose-sensing-server/Cargo.toml` and `src/main.rs`. The conflict surface is **disjoint by section**:
+
+| File | ADR-110 region | ADR-115 region |
+|---|---|---|
+| `Cargo.toml` | `[dependencies]` — `wifi-densepose-hardware = { path = "../wifi-densepose-hardware" }` near the existing `wifi-densepose-signal` line | `[dependencies]` — `rumqttc` block below + `[features]` block at end |
+| `main.rs` | `NodeState` fields + `impl NodeState` helpers + `update_csi_fps_ema` free fn + `fps_ema_tests` module + `udp_receiver_task` magic dispatch | (TBD per ADR-115 P-plan) |
+
+A merge between the two branches should be **clean line-merge** since the regions don't overlap. If git ever reports a real conflict in either of these files, that means one branch has drifted into the other's region — investigate before resolving blindly.
+
+## Quick test commands (verify either branch is sane)
+
+```bash
+# Rust workspace (run from v2/)
+cd v2
+cargo test --workspace --no-default-features --lib       # 1437 tests at iter 22, 0 failures
+
+# Python ADR-110 host decoder (from repo root)
+python -m pytest archive/v1/tests/unit/test_esp32_binary_parser.py::TestSyncPacketParser -v
+
+# Cross-language wire-format gate (the iter 21 pin)
+cargo test -p wifi-densepose-hardware --no-default-features --lib sync_packet::tests::canonical_wire_bytes_match_python_decoder
+python -m pytest archive/v1/tests/unit/test_esp32_binary_parser.py::TestSyncPacketParser::test_canonical_wire_bytes_match_rust_decoder -v
+```
+
+If either side of the canonical-wire-bytes pair fails alone, the OTHER decoder has drifted from the wire format — investigate that decoder first, not the failing test.
+
+## Future-proofing
+
+- When the ADR-115 agent ships `feat/adr-115-ha-mqtt-matter` to main and ADR-110 also ships, merge `main` into `adr-110-esp32c6` (or vice versa) and re-run both test suites. The disjoint-region structure above should make the merge a no-conflict fast-forward.
+- When a third agent picks up either ADR, point them at this file before they start editing shared files.
+- If a /loop drives autonomous iterations and hits a cross-branch checkout, the recovery procedure is in iter 18's commit message (`2997165bc`) — stash on the foreign branch, `git checkout` home, replay the iter locally.