feat(jpeg): simplify decoder example and add pytest coverage

examples/peripherals/jpeg/jpeg_encode/README.md

@@ -50,6 +50,19 @@ The accompanying `pytest_jpeg_encode.py` script captures the `JPEG_META` and `JP
 
 It also compares the generated JPEG with `golden_output.jpeg`. This turns the example into both a functional regression test and a host-side artifact generator that makes the encoded result easy to inspect.
 
+## Running Pytest Locally And Viewing The Image
+
+To run the pytest helper locally on hardware, build the example for your target first, then invoke the test script with the target and serial port:
+
+```bash
+idf.py set-target esp32p4 build
+pytest --target esp32p4 --port PORT pytest_jpeg_encode.py
+```
+
+Replace `esp32p4` with another supported target such as `esp32s31` when needed.
+
+`pytest-embedded` stores per-test logs under `$IDF_PATH/pytest-embedded/`. The script writes the reconstructed image to `jpeg_encode_result.jpeg` inside that test log directory, so after the test finishes you can open the generated JPEG locally with any image viewer to inspect the encoded output.
+
 ## Replacing The Embedded RGB Asset
 
 If you want to regenerate a compatible raw frame from another input image, one simple workflow is: