[ci] Move pregen steps into a composite action (#7474)

This ensures that complete uniformity in how the generation scripts are run. All dependencies and scripts are set up in the exact same way, each time. The old pregen_all script has been removed and moved into the composite action to ensure failed scripts will always fail the job.

.github/actions/pregen/action.yml

@@ -0,0 +1,61 @@
+name: 'Setup and run pregeneration'
+description: 'Sets up the dependencies needed to generate generated files and runs all generation scripts'
+
+runs:
+  using: "composite"
+  steps:
+    - name: Set up Python 3.12
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.12'
+    - name: Install jinja and protobuf
+      run: python -m pip install jinja2 protobuf grpcio-tools
+      shell: bash
+    - name: Install protobuf dependencies
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y protobuf-compiler
+        wget https://github.com/HebiRobotics/QuickBuffers/releases/download/1.3.3/protoc-gen-quickbuf-1.3.3-linux-x86_64.exe
+        chmod +x protoc-gen-quickbuf-1.3.3-linux-x86_64.exe
+      shell: bash
+    - name: Regenerate hal
+      run: ./hal/generate_usage_reporting.py
+      shell: bash
+
+    - name: Regenerate ntcore
+      run: ./ntcore/generate_topics.py
+      shell: bash
+
+    - name: Regenerate imgui
+      run: |
+        ./thirdparty/imgui_suite/generate_fonts.sh
+        ./thirdparty/imgui_suite/generate_gl3w.py
+      shell: bash
+
+    - name: Regenerate HIDs
+      run: |
+        ./wpilibc/generate_hids.py
+        ./wpilibj/generate_hids.py
+        ./wpilibNewCommands/generate_hids.py
+      shell: bash
+
+    - name: Regenerate PWM motor controllers
+      run: |
+        ./wpilibc/generate_pwm_motor_controllers.py
+        ./wpilibj/generate_pwm_motor_controllers.py
+      shell: bash
+
+    - name: Regenerate wpimath
+      run: |
+        ./wpimath/generate_nanopb.py
+        ./wpimath/generate_numbers.py
+        ./wpimath/generate_quickbuf.py --quickbuf_plugin protoc-gen-quickbuf-1.3.3-linux-x86_64.exe
+      shell: bash
+
+    - name: Regenerate wpiunits
+      run: ./wpiunits/generate_units.py
+      shell: bash
+
+    - name: Regenerate wpiutil nanopb
+      run: ./wpiutil/generate_nanopb.py
+      shell: bash