docs: refine Greptile documentation review context

greptile.json

@@ -23,5 +23,29 @@
     "included": true,
     "collapsible": true,
     "defaultOpen": true
+  },
+  "customContext": {
+    "rules": [
+      {
+        "rule": "Before reporting an internal Fern documentation link as broken, inspect the pull request together with its target branch and resolve the route through docs/index.yml. Do not infer that a route is missing solely because its destination is absent from the source branch. Treat the Check Fern docs CI job, which runs make docs-fern-strict, as the authoritative link-validation result. Only report a link after demonstrating a failure in the merged tree or rendered preview.",
+        "scope": ["docs/**", "fern/**"]
+      },
+      {
+        "rule": "Before claiming that a release is absent from CHANGELOG.md, inspect the target branch or proposed merge result because changelog entries are generated by the release workflow.",
+        "scope": ["docs/about/release-notes.mdx"]
+      }
+    ],
+    "files": [
+      {
+        "path": "CONTRIBUTING.md",
+        "description": "Repository documentation validation requirements",
+        "scope": ["docs/**", "fern/**"]
+      },
+      {
+        "path": ".github/workflows/docs-build.yaml",
+        "description": "Authoritative Fern documentation CI workflow",
+        "scope": ["docs/**", "fern/**"]
+      }
+    ]
   }
 }