ci: Update actions/checkout to v5 for Node.js 24 compatibility

Node.js 20 actions are deprecated and will be forced to Node.js 24
starting June 2nd, 2026. Update all workflow files and the generator
script to use actions/checkout@v5 which supports Node.js 24.

Author: gin66

.github/workflows/arduino_lint.yml

@@ -3,7 +3,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: arduino/arduino-lint-action@v1
         with:
           library-manager: update

.github/workflows/build_arduino_examples_matrix.yml

@@ -77,7 +77,7 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v5
     - name: Make directories
       run: bash extras/scripts/build-pio-dirs.sh
     - name: Build on PlatformIO

.github/workflows/build_examples_esp32_tasmota_2_0_15.yml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v5
     - name: Make directories
       run: bash extras/scripts/build-pio-dirs.sh
     - name: Build on PlatformIO

.github/workflows/build_examples_esp_idf_project.yml

@@ -21,7 +21,7 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v5
     - name: esp-idf build
       uses: espressif/esp-idf-ci-action@v1
       with:

.github/workflows/build_idf_examples_matrix.yml

@@ -60,7 +60,7 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v5
     - name: Make directories
       run: bash extras/scripts/build-pio-dirs.sh
     - name: Build on PlatformIO

.github/workflows/test.yml

@@ -12,6 +12,6 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - name: make
       run: make -C extras/tests/pc_based

.github/workflows/test_avr.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - name: get platformio
       run: curl -fsSL https://raw.githubusercontent.com/platformio/platformio-core-installer/master/get-platformio.py -o get-platformio.py
     - name: install platformio

extras/scripts/generate_build_configs.py

@@ -203,7 +203,7 @@ def generate_workflow_yml(workflow_name: str, workflow_config: dict[str, Any]) -
             "",
             "    steps:",
             "    - name: Checkout",
-            "      uses: actions/checkout@v4",
+            "      uses: actions/checkout@v5",
             "    - name: Make directories",
             "      run: bash extras/scripts/build-pio-dirs.sh",
             "    - name: Build on PlatformIO",