Add options for review prompt style (#24166)

* Add script for testing genai review prompts

* Add option for prompt styling

* Add tests

* Update docs

testing-scripts/genai-review-examples/README.md

@@ -0,0 +1,23 @@
+# GenAI Review Examples
+
+Local example data for `testing-scripts/genai_review_tester.py`.
+
+Each subfolder here should be a copy of a debug output folder saved by
+Frigate when `review.genai.debug_save_thumbnails: True` is enabled. Those
+folders are written to `clips/genai-requests/<review_id>/` and contain:
+
+- Numbered frame images (`0.jpg`, `1.jpg`, ... or `.webp`) as sent to the
+  GenAI provider
+- `prompt.txt` with the exact prompt Frigate built for the request
+- `response.txt` with the provider's response (not used by the tester)
+
+Copy folders in, optionally rename them to something memorable (for example
+`driveway-night-delivery`), then run the tester from the repo root:
+
+```bash
+python3 testing-scripts/genai_review_tester.py
+```
+
+Everything in this folder except this README is gitignored, since the frames
+come from real cameras. Provider settings for the tester are stored here in
+`.settings.json`.