custom FW repos code generation process toolset

[rusefillc]

problem statement:

at the moment in https://github.com/rusefi/fw-custom-example/ we invoke

      - name: Gen Config
        working-directory: ext/rusefi/firmware
        run: |
          bash gen_config_board.sh ../../.. ${{inputs.shortBoardName}}

which modifies files within ext/rusefi folder

further compilation steps in fw-custom-example read those ext/rusefi generated files, and then we have a hack of

      - name: Push Config
        run: |
          mkdir -p generated
          cp ext/rusefi/firmware/controllers/generated/rusefi_generated.h   generated
          cp ext/rusefi/firmware/controllers/generated/signature_${{inputs.shortBoardName}}.h generated
          cp ext/rusefi/firmware/tunerstudio/generated/rusefi_${{inputs.shortBoardName}}.ini  generated
          git config --local user.email "action@github.com"
          git config --local user.name "GitHub git update Action"
          git add generated/*
          git commit -am "GHA Automation Snapshot just for reference"
          git status

problem: that's a mess

it's desired to have only one copy of fw-custom-example files outside of ext/rusefi

[rusefillc]

#if !EFI_UNIT_TEST
#define SIGNATURE_H_FILENAME QUOTE(SIGNATURE_NAME SHORT_BOARD_NAME SIGNATURE_EXT)
#include SIGNATURE_H_FILENAME

#pragma message ("TS_SIGNATURE: " TS_SIGNATURE)

[rusefillc]

6fc7581

[rusefillc]

Done!!!