feat: update CAN integration and T2G seat firmware

firmware/t2g/README.md

@@ -1,37 +1,44 @@
-# T2G seat-controller firmware
+# Self-contained T2G seat-controller firmware
 
-`Seat_Controller_demo/` is the repository-owned IAR interface project for the
-physical seat bench. It combines the verified heater, fan and four-motor demos
-and is the only firmware accepted by the hardware executor.
+`Seat_Controller_demo/` is the repository-owned IAR project used by the real
+seat-bench executor. It contains the 2026-07-30 heater, ventilation, four-axis
+motion, SMV8 position memory, Hall feedback and ADC current-diagnostic code.
 
-The Infineon/T2G vendor library is intentionally not duplicated here. The IAR
-project keeps its original relative `common/` and `tviibh8m/` references;
-`tools/build_seat_firmware.ps1` stages the repository project beside junctions
-to `COGNITIVE_AGENT_T2G_SDK_ROOT`, builds it, and copies only the resulting
-`Seat_Controller_demo.hex` and `Seat_Controller_demo.out` back into the
-repository.
+The matching Cypress 7.9.0 build dependencies are vendored beside it:
 
-```powershell
-powershell -ExecutionPolicy Bypass -File .\tools\build_seat_firmware.ps1 -Profile combined
+```text
+firmware/t2g/
+├── common/
+├── tviibh8m/
+└── Seat_Controller_demo/
 ```
 
-The build script never opens a debug probe or flashes a target. Physical
-programming is performed only by an authorized `execution_mode=hardware`
-request when `COGNITIVE_AGENT_SEAT_AUTO_FLASH_ENABLED=true` and the CAN
-identity handshake does not match the repository firmware.
+This preserves the IAR project's `../../common` and `../../tviibh8m` paths and
+removes any dependency on the original Desktop SDK directory. The applicable
+vendor terms are retained in `CYPRESS_SDK_LICENSE.txt`. An IAR installation is
+still a toolchain prerequisite, just as the ZLG driver remains a CAN-adapter
+prerequisite; neither is project source data.
 
-Automatic programming uses `IAR/Seat_Controller_program.mac`, not the
-interactive-debug `Seat_Controller_demo.mac`. The automatic-programming macro
-forces motor, fan and heater outputs low before download, clears the retained
-debug-session marker, and uses a bounded Download-and-Debug handoff with
-`--leave_target_running`. `--download_only` is intentionally not used because
-it leaves the CM0+ stopped after programming.
+Build without flashing:
 
-Firmware identity protocol:
+```powershell
+powershell -ExecutionPolicy Bypass -File .\tools\build_seat_firmware.ps1
+```
 
-- request: `0x304`, `53 45 41 54 01 00 00 00`
-- expected response: `0x305`, `53 45 41 54 01 01 00 3F`
+Set `COGNITIVE_AGENT_IAR_BUILD` or pass `-IarBuild` when `iarbuild.exe` is not
+at a standard location. The script stages the project beside repository-local
+vendor junctions, copies the resulting HEX/OUT back, removes build products,
+and never opens a debug probe.
 
-The response identifies protocol 1, firmware 1.1.0 and the combined capability
-mask. It is a non-actuating readiness probe and is checked before any seat
-control frame is sent.
+The latest firmware uses periodic CAN `0x304`/`0x305` for motor and thermal
+current diagnostics. The backend therefore verifies it passively by observing
+`0x301` through `0x305`, `0x4FA`, all four motor IDs and MaxHall
+`480/374/917/647`; it sends no identity request and no actuator frame during
+verification.
+
+When real hardware execution is enabled, automatic programming defaults to
+enabled and uses `IAR/Seat_Controller_program.mac` to force outputs safe before
+download.  A missing protocol signature triggers programming, a boot wait and
+passive re-verification before the original request continues.  Set
+`COGNITIVE_AGENT_SEAT_AUTO_FLASH_ENABLED=false` to opt out explicitly; dry-run
+execution never programs hardware.