State dir clarifications

.woodpecker/pr-build.yaml

@@ -9,10 +9,21 @@
 # Reports pass/fail status back to Gitea, so it shows up as a required check on
 # the PR.
 
+# Doc-only changes can't affect the image, so they don't trigger the build.
+# NOTE: if Gitea is ever configured to REQUIRE this check for merging, a
+# doc-only PR will have no check at all — exempt such PRs or merge manually.
+# Renovate PRs always touch the Dockerfile or pipeline files, so the
+# automerge gate is unaffected by these exclusions.
 when:
   - event: pull_request
+    path:
+      exclude: &doc_paths
+        - '**/*.md'
+        - 'docs/**'
   - event: push
     branch: main
+    path:
+      exclude: *doc_paths
 
 steps:
   - name: Build all arches (no push)