ci: only run sync idempotency when relevant paths change

Author: yaniv-golan

.github/workflows/tests.yml

@@ -15,6 +15,20 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v6
 
+      - name: Detect changes
+        id: changes
+        uses: dorny/paths-filter@v3
+        with:
+          filters: |
+            v1:
+              - 'tools/v1_sync_pipeline/**'
+              - 'docs/v1/**'
+            v2:
+              - 'tools/v2_sync_pipeline/**'
+              - 'docs/v2/**'
+            workflows:
+              - '.github/workflows/**'
+
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
@@ -27,11 +41,13 @@ jobs:
           pip install -r requirements-ci.txt
 
       - name: Ensure v1 sync script is idempotent
+        if: steps.changes.outputs.v1 == 'true' || steps.changes.outputs.workflows == 'true'
         run: |
           python tools/v1_sync_pipeline/sync_v1_docs.py --fail-on-diff --summary-file "$GITHUB_STEP_SUMMARY"
           python tools/v1_sync_pipeline/qa/check_links.py docs/v1/affinity_api_docs.md
 
       - name: Ensure v2 sync script is idempotent
+        if: steps.changes.outputs.v2 == 'true' || steps.changes.outputs.workflows == 'true'
         run: |
           python tools/v2_sync_pipeline/sync_v2_docs.py --fail-on-diff --snapshot-dir tmp/v2
           python tools/v1_sync_pipeline/qa/check_links.py docs/v2/affinity_api_docs.md