Switch to esp32_16MB_V4_M_eth_debug build for QEMU tests

Changed all scripts and documentation to use the new debug ethernet
build environment as requested:

Workflow changes:
- Build: esp32_16MB_V4_M_eth_debug (was esp32_4MB_V4_S_eth)
- PlatformIO cache key updated
- Firmware artifact paths updated

Script changes:
- run-qemu.sh: Default firmware dir updated
- monitor-qemu.py: Default firmware dir updated

Documentation changes:
- e2e-tests/README.md: Updated commands and descriptions
- docs/QEMU-ISSUES.md: Updated build info, added debug benefits

The esp32_16MB_V4_M_eth_debug build provides:
- 16MB flash (vs 4MB)
- V4 Mainline variant (vs Sound Reactive)
- Ethernet with ESP32-POE config
- Debug capabilities for better crash analysis
- WiFi disabled (required for QEMU)

Co-authored-by: softhack007 <91616163+softhack007@users.noreply.github.com>

Author: Copilot

.github/scripts/monitor-qemu.py

@@ -89,5 +89,5 @@ def monitor_output(firmware_dir):
                 exception_lines = []
 
 if __name__ == '__main__':
-    firmware_dir = sys.argv[1] if len(sys.argv) > 1 else '.pio/build/esp32_4MB_V4_S_eth'
+    firmware_dir = sys.argv[1] if len(sys.argv) > 1 else '.pio/build/esp32_16MB_V4_M_eth_debug'
     monitor_output(firmware_dir)

.github/scripts/run-qemu.sh

@@ -9,7 +9,7 @@
 
 set -e
 
-FIRMWARE_DIR="${1:-.pio/build/esp32_4MB_V4_S_eth}"
+FIRMWARE_DIR="${1:-.pio/build/esp32_16MB_V4_M_eth_debug}"
 QEMU_DIR="${2:-qemu-esp32}"
 HTTP_PORT="${3:-8080}"  # Default to 8080 (non-privileged port)
 

.github/workflows/qemu-e2e-test.yml

@@ -27,9 +27,9 @@ jobs:
         uses: actions/cache@v4
         with:
           path: ~/.platformio
-          key: ${{ runner.os }}-pio-esp32_4MB_V4_S_eth-${{ hashFiles('**/platformio.ini') }}
+          key: ${{ runner.os }}-pio-esp32_16MB_V4_M_eth_debug-${{ hashFiles('**/platformio.ini') }}
           restore-keys: |
-            ${{ runner.os }}-pio-esp32_4MB_V4_S_eth-
+            ${{ runner.os }}-pio-esp32_16MB_V4_M_eth_debug-
       
       - name: Set up Python
         uses: actions/setup-python@v5
@@ -52,13 +52,13 @@ jobs:
         run: npm run build
 
       - name: Build ESP32 firmware
-        run: pio run -e esp32_4MB_V4_S_eth
+        run: pio run -e esp32_16MB_V4_M_eth_debug
 
       - name: Upload firmware artifacts
         uses: actions/upload-artifact@v4
         with:
           name: esp32-firmware
-          path: .pio/build/esp32_4MB_V4_S_eth/
+          path: .pio/build/esp32_16MB_V4_M_eth_debug/
           retention-days: 1
 
   # Job 2: Test with QEMU ESP32
@@ -85,7 +85,7 @@ jobs:
         uses: actions/download-artifact@v4
         with:
           name: esp32-firmware
-          path: .pio/build/esp32_4MB_V4_S_eth/
+          path: .pio/build/esp32_16MB_V4_M_eth_debug/
 
       - name: Install Node.js dependencies
         run: npm ci
@@ -116,7 +116,7 @@ jobs:
       - name: Start QEMU with WLED firmware in background
         run: |
           chmod +x .github/scripts/run-qemu.sh
-          bash .github/scripts/run-qemu.sh .pio/build/esp32_4MB_V4_S_eth qemu-esp32 8080 > qemu-output.log 2>&1 &
+          bash .github/scripts/run-qemu.sh .pio/build/esp32_16MB_V4_M_eth_debug qemu-esp32 8080 > qemu-output.log 2>&1 &
           echo "Waiting for QEMU to start and WLED to boot..."
           sleep 45
       

docs/QEMU-ISSUES.md

@@ -2,16 +2,17 @@
 
 ## Build Configuration
 
-**Important**: QEMU testing uses the **V4 Sound Reactive ethernet build** (`esp32_4MB_V4_S_eth`).
+**Important**: QEMU testing uses the **V4 Mainline ethernet debug build** (`esp32_16MB_V4_M_eth_debug`).
 
-### Why esp32_4MB_V4_S_eth Build?
+### Why esp32_16MB_V4_M_eth_debug Build?
 - WiFi hardware is not emulated in QEMU
 - WiFi initialization causes crashes in QEMU
 - Ethernet build uses `WLED_USE_ETHERNET` flag
 - Disables ESP-NOW with `WLED_DISABLE_ESPNOW` (requires WiFi)
 - Uses ESP32-POE board configuration (`WLED_ETH_DEFAULT=2`)
 - Allows network functionality without WiFi hardware
 - HTTP server works via emulated ethernet (open_eth model)
+- Debug build provides better crash analysis capabilities
 
 ### Ethernet Configuration for QEMU
 The build uses ESP32-POE board configuration (index 2):
@@ -76,7 +77,7 @@ ESP32 QEMU emulation is not perfect and has several known limitations:
 **Symptom**: Crashes when accessing I2C, SPI, or other peripherals  
 **Cause**: Peripheral emulation is incomplete  
 **Analysis**: Check which peripheral is being accessed in the backtrace  
-**Solution**: These may be QEMU-specific issues
+**Solution**: These may be QEMU-specific issues, use ethernet debug build for better diagnostics
 
 #### 3. Real Firmware Bugs
 **Symptom**: Crashes in application code (not hardware access)  

e2e-tests/README.md

@@ -31,12 +31,12 @@ pip install -r requirements.txt
 
 Test the actual firmware running in QEMU ESP32 emulator:
 
-**Important**: Use the V4 Sound Reactive ethernet build for QEMU testing, as WiFi is not emulated and causes crashes.
+**Important**: Use the V4 Mainline ethernet debug build for QEMU testing, as WiFi is not emulated and causes crashes.
 
 1. **Build the firmware**:
    ```bash
    npm run build  # Build web UI
-   pio run -e esp32_4MB_V4_S_eth  # Build V4 SR ethernet firmware (WiFi disabled, 15+ min first time)
+   pio run -e esp32_16MB_V4_M_eth_debug  # Build V4 M ethernet debug firmware (WiFi disabled, 15+ min first time)
    ```
 
 2. **Setup QEMU** (first time only):
@@ -46,7 +46,7 @@ Test the actual firmware running in QEMU ESP32 emulator:
 
 3. **Run firmware in QEMU** (in a separate terminal):
    ```bash
-   bash .github/scripts/run-qemu.sh .pio/build/esp32_4MB_V4_S_eth qemu-esp32 8080
+   bash .github/scripts/run-qemu.sh .pio/build/esp32_16MB_V4_M_eth_debug qemu-esp32 8080
    ```
 
    Wait ~30-45 seconds for ESP32 to boot and start the web server.