ci: stamp VCS_DATE at build time (firmware version date)

The rusefi submodule is pinned, so its committed date_stamp.h (VCS_DATE,
the firmware version date shown in TunerStudio) is frozen while the TS
signature date is generated fresh each build - making the version look
stale (e.g. 20260621). Stamp date_stamp.h with today's date before the
build in nightly-release, build-matrix and the local build_boards.sh, so
the firmware version reflects the actual build date. The submodule
set-date.yaml stays disabled (it can't reach the pinned build anyway).

Author: amrikarisma

.github/workflows/build-matrix.yaml

@@ -57,6 +57,12 @@ jobs:
           git config --global url."https://x-access-token:${{ secrets.MY_REPO_PAT }}@github.com/".insteadOf "git@github.com:"
           git submodule update --init --force
 
+      # The submodule is pinned, so its date_stamp.h (VCS_DATE, the firmware
+      # version date) is frozen. Stamp today's date so builds report the actual
+      # build date instead of a stale one. Mirrors ext/rusefi set-date.yaml.
+      - name: Stamp firmware build date (VCS_DATE)
+        run: printf '#pragma once\n#define VCS_DATE %s\n' "$(date +%Y%m%d)" > ext/rusefi/firmware/controllers/date_stamp.h
+
       - name: Set run variables
         id: set-variables
         run: |

.github/workflows/nightly-release.yaml

@@ -62,6 +62,13 @@ jobs:
           git config --global url."https://x-access-token:${{ secrets.MY_REPO_PAT }}@github.com/".insteadOf "git@github.com:"
           git submodule update --init --force
 
+      # The submodule is checked out at a pinned commit, so its date_stamp.h
+      # (VCS_DATE, the firmware version date) is frozen at whenever the submodule
+      # last ran set-date. Stamp today's date here so nightly builds report the
+      # actual build date instead of a stale one. Mirrors ext/rusefi set-date.yaml.
+      - name: Stamp firmware build date (VCS_DATE)
+        run: printf '#pragma once\n#define VCS_DATE %s\n' "$(date +%Y%m%d)" > ext/rusefi/firmware/controllers/date_stamp.h
+
       - uses: ./ext/rusefi/.github/workflows/custom-board-build
         with:
           meta_info: ${{ matrix.meta-info }}

build_boards.sh

@@ -56,6 +56,12 @@ fi
 
 echo "=== Boards to build: ${BOARDS[*]} ==="
 
+# The rusefi submodule's date_stamp.h (VCS_DATE, the firmware version date) is
+# frozen at whenever set-date last ran. Stamp today's date so local builds
+# report the actual build date instead of a stale one, matching the CI stamp.
+printf '#pragma once\n#define VCS_DATE %s\n' "$(date +%Y%m%d)" > "$REPO_ROOT/ext/rusefi/firmware/controllers/date_stamp.h"
+echo "=== Stamped VCS_DATE=$(date +%Y%m%d) into ext/rusefi/firmware/controllers/date_stamp.h ==="
+
 for BOARD in "${BOARDS[@]}"; do
     META="$REPO_ROOT/boards/$BOARD/meta-info.env"
     if [ ! -f "$META" ]; then