Harden CI automation and add Dependabot for Actions

Author: warrentc3

.github/dependabot.yml

@@ -0,0 +1,14 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "monday"
+      time: "06:00"
+      timezone: "UTC"
+    open-pull-requests-limit: 5
+    groups:
+      github-actions-dependencies:
+        patterns:
+          - "*"

.github/workflows/spec-structure.yml

@@ -3,8 +3,28 @@ name: Spec Directory Structure
 on:
   push:
     branches: [main]
+    paths:
+      - "catalog.json"
+      - "index.html"
+      - "scripts/**"
+      - ".github/workflows/**"
+      - "*/index.html"
+      - "*-*/**/*-api_openapi-v*.json"
+      - "*/*-api_openapi-v*.json"
   pull_request:
     branches: [main]
+    paths:
+      - "catalog.json"
+      - "index.html"
+      - "scripts/**"
+      - ".github/workflows/**"
+      - "*/index.html"
+      - "*-*/**/*-api_openapi-v*.json"
+      - "*/*-api_openapi-v*.json"
+
+concurrency:
+  group: spec-structure-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
 
 permissions:
   contents: write