ci: add conditional job for OpenAPI linting based on file changes; update README with workflow details

.gitea/README.md

@@ -2,6 +2,8 @@
 
 В репозитории включён workflow [workflows/ci.yaml](workflows/ci.yaml).
 
+Job **openapi** (Redocly) запускается только если в коммите или PR изменились `docs/openapi.yaml` или `redocly.yaml`; иначе шаг пропускается. Остальные jobs (`go`, `bird2`) выполняются как раньше.
+
 Требования к runner:
 
 - Метка `ubuntu-latest` (или измените `runs-on` под свои labels).

.gitea/workflows/ci.yaml

@@ -7,7 +7,50 @@ on:
     branches: [main, master]
 
 jobs:
+  changes:
+    runs-on: ubuntu-latest
+    outputs:
+      openapi: ${{ steps.openapi.outputs.changed }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - id: openapi
+        name: Detect OpenAPI-related file changes
+        run: |
+          set -euo pipefail
+          PATHS="docs/openapi.yaml redocly.yaml"
+          changed=false
+
+          if [ "${{ github.event_name }}" = "pull_request" ]; then
+            base="${{ github.event.pull_request.base.sha }}"
+            head="${{ github.event.pull_request.head.sha }}"
+            if git diff --name-only "$base" "$head" -- $PATHS | grep -q .; then
+              changed=true
+            fi
+          else
+            before="${{ github.event.before }}"
+            after="${{ github.sha }}"
+            if [ -n "$before" ] && [ "$before" != "0000000000000000000000000000000000000000" ]; then
+              if git diff --name-only "$before" "$after" -- $PATHS | grep -q .; then
+                changed=true
+              fi
+            elif git rev-parse --verify HEAD~1 >/dev/null 2>&1; then
+              if git diff --name-only HEAD~1 HEAD -- $PATHS | grep -q .; then
+                changed=true
+              fi
+            else
+              # Нет родителя (первый коммит / тонкий clone) — линт OpenAPI выполняем один раз
+              changed=true
+            fi
+          fi
+
+          echo "changed=$changed" >> "$GITHUB_OUTPUT"
+          echo "OpenAPI lint will run: $changed"
+
   openapi:
+    needs: [changes]
+    if: needs.changes.outputs.openapi == 'true'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4

internal/birdfmt/scenarios_test.go

@@ -21,8 +21,8 @@ func TestBirdScenarioPaths_Table(t *testing.T) {
 		"empty_static",
 		"filter_export",
 		"large_prefix_list",
-		"mixed_static_bgp",
 		"minimal",
+		"mixed_static_bgp",
 		"static_ipv4",
 		"with_include",
 	}