docs(github): proof-of-fix template shows only the latest run as Before/After with nested cases

.github/pull_request_template.md

@@ -65,11 +65,35 @@ If you're seeing a delay in your PR being merged, ping the LiteLLM Team on [Slac
 
 <!-- Include screenshots, screen recordings, or command (e.g., curl) + output demonstrating that your changes work as expected
      The proof must be completely e2e with no mocks, using, for example, actual LLM calls costing real $. `pytest` commands are not enough
-     For bug fixes: show reproduction before the fix and passing behavior after
-     Include the commit hash each proof was captured at, for both the before and the after runs
-     If the change applies to all three LLM endpoints (/v1/responses, /v1/chat/completions, /v1/messages), include proof for every single one of them, not just one
-     For new features: show the feature working end-to-end
-     For UI changes: include before/after screenshots -->
+     Show ONLY the latest run: capture Before at the merge base and After at the PR's current tip, and when new commits change behavior, replace this whole section with the fresh run instead of stacking it on top of older ones
+     Structure the section exactly as below: Before and After one heading level below this section, each naming the commit hash it was captured at, one lower-level heading per case inside each, the same case names in the same order on both sides; shared setup (config, payloads) goes above Before, and with a single case, drop the case headings and number the steps directly
+
+### Before (<hash>)
+
+#### <case 1>
+
+1. ...
+2. ...
+
+#### <case 2>
+
+1. ...
+
+### After (<hash>)
+
+#### <case 1>
+
+1. ...
+2. ...
+
+#### <case 2>
+
+1. ...
+
+     For bug fixes: Before shows the reproduction, After shows the same steps passing
+     For new features: Before shows the capability missing, After shows it working end-to-end
+     If the change applies to all three LLM endpoints (/v1/responses, /v1/chat/completions, /v1/messages), make each endpoint its own case, not just one
+     For UI changes: before/after screenshots under the same headings -->
 
 ## Type