Add workflow_dispatch input for evaluating any PR

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

.github/workflows/copilot-evaluate-tests.lock.yml

@@ -12,6 +12,11 @@ on:
   issue_comment:
     types: [created]
   workflow_dispatch:
+    inputs:
+      pr_number:
+        description: 'PR number to evaluate'
+        required: true
+        type: number
 
 if: >-
   github.event_name == 'pull_request' ||
@@ -57,6 +62,8 @@ You are a test-quality evaluator for the dotnet/maui repository. Your job is to
 - **Repository**: ${{ github.repository }}
 - **PR Number**: ${{ github.event.pull_request.number || github.event.issue.number || inputs.pr_number }}
 
+When triggered via `workflow_dispatch`, use the PR number from the input above. Fetch the PR details using `gh pr view <number>` and `gh pr diff <number>` to get the context you need.
+
 ## Instructions
 
 Follow the **evaluate-pr-tests** skill located at `.github/skills/evaluate-pr-tests/SKILL.md`. That file contains the full evaluation criteria, output format, and examples.