merge: main into feat/adr-115-ha-mqtt-matter — resolve CHANGELOG + ADR-115.md

Brings the new main (with ADR-110 merged, commit 00a234eda) into the
ADR-115 branch so PR #778 can be merge-able.

Conflicts:

  CHANGELOG.md
    Both branches added entries to the [Unreleased] → Added section.
    Resolution: keep BOTH — the ADR-115 HA+Matter entry first
    (front-facing, this branch's contribution), then the ADR-110
    waves 1-5 entries from main (already merged, historical record).
    No content lost.

  docs/adr/ADR-115-home-assistant-integration.md
    Add/add conflict — main got the file in its earlier shape
    (Status: Proposed, Tracking issue: TBD) via the iter-17-19
    cross-branch checkout incident on the adr-110 branch that ended
    up merged via PR #764. This branch's version has the current
    Accepted status and the real PR #778 link.
    Resolution: take this branch's authoritative ADR-115 content.

The 3 .rs files I had flagged in PR #778 comment 4526344883
(lib.rs, esp32_parser.rs, tracker_bridge.rs) AUTO-MERGED cleanly —
this branch's local state already had the equivalent shape.

Verification: cargo check -p wifi-densepose-sensing-server
--no-default-features → green (5 warnings, 0 errors).

Co-Authored-By: claude-flow <ruv@ruv.net>

.github/workflows/firmware-ci.yml

@@ -38,7 +38,7 @@ jobs:
           echo "version.txt matches the release tag."
 
   build:
-    name: Build ESP32-S3 Firmware (${{ matrix.variant }})
+    name: Build firmware (${{ matrix.target }} / ${{ matrix.variant }})
     runs-on: ubuntu-latest
     container:
       image: espressif/idf:v5.4
@@ -47,17 +47,27 @@ jobs:
       matrix:
         include:
           - variant: 8mb
+            target: esp32s3
             sdkconfig: sdkconfig.defaults
             partition_table_name: partitions_display.csv
             size_limit_kb: 1100
             artifact_app: esp32-csi-node.bin
             artifact_pt: partition-table.bin
           - variant: 4mb
+            target: esp32s3
             sdkconfig: sdkconfig.defaults.4mb
             partition_table_name: partitions_4mb.csv
             size_limit_kb: 1100
             artifact_app: esp32-csi-node-4mb.bin
             artifact_pt: partition-table-4mb.bin
+          # ADR-110: ESP32-C6 research target (Wi-Fi 6 / 802.15.4 / TWT / LP-core)
+          - variant: c6-4mb
+            target: esp32c6
+            sdkconfig: sdkconfig.defaults
+            partition_table_name: partitions_4mb.csv
+            size_limit_kb: 1100
+            artifact_app: esp32-csi-node-c6.bin
+            artifact_pt: partition-table-c6.bin
 
     steps:
       - uses: actions/checkout@v4
@@ -66,12 +76,22 @@ jobs:
         working-directory: firmware/esp32-csi-node
         run: |
           . $IDF_PATH/export.sh
-          if [ "${{ matrix.variant }}" != "8mb" ]; then
+          # 4mb variant supplies its own sdkconfig.defaults overlay.
+          # c6-4mb variant relies on the auto-applied sdkconfig.defaults.esp32c6
+          # overlay (ESP-IDF auto-loads sdkconfig.defaults.$TARGET when present).
+          if [ "${{ matrix.variant }}" = "4mb" ]; then
             cp "${{ matrix.sdkconfig }}" sdkconfig.defaults
           fi
-          idf.py set-target esp32s3
+          idf.py set-target ${{ matrix.target }}
           idf.py build
 
+      - name: Build and run host-side ADR-110 unit tests
+        if: matrix.variant == 'c6-4mb'
+        working-directory: firmware/esp32-csi-node/test
+        run: |
+          make test_adr110
+          ./test_adr110
+
       - name: Verify binary size (< ${{ matrix.size_limit_kb }} KB gate)
         working-directory: firmware/esp32-csi-node
         run: |