feat(enrich): add metadata enrichment queue UI

Home page shows "Needs metadata" card when incomplete documents exist.
/enrich list shows all incomplete documents; /enrich/[id] provides a
split PDF-preview + compact form view with Skip / Save / Save & reviewed
actions that auto-advance through the queue.

New document page gets Save vs Save & reviewed split. Edit page gets
"Mark for review" secondary button to push a document back into the queue.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/lib/generated/api.ts

@@ -468,6 +468,54 @@ export interface paths {
         patch?: never;
         trace?: never;
     };
+    "/api/documents/incomplete-count": {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        get: operations["getIncompleteCount"];
+        put?: never;
+        post?: never;
+        delete?: never;
+        options?: never;
+        head?: never;
+        patch?: never;
+        trace?: never;
+    };
+    "/api/documents/incomplete": {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        get: operations["getIncomplete"];
+        put?: never;
+        post?: never;
+        delete?: never;
+        options?: never;
+        head?: never;
+        patch?: never;
+        trace?: never;
+    };
+    "/api/documents/incomplete/next": {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        get: operations["getNextIncomplete"];
+        put?: never;
+        post?: never;
+        delete?: never;
+        options?: never;
+        head?: never;
+        patch?: never;
+        trace?: never;
+    };
     "/api/documents/search": {
         parameters: {
             query?: never;
@@ -1819,6 +1867,77 @@ export interface operations {
             };
         };
     };
+    getIncompleteCount: {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        requestBody?: never;
+        responses: {
+            /** @description OK */
+            200: {
+                headers: {
+                    [name: string]: unknown;
+                };
+                content: {
+                    "*/*": {
+                        count: number;
+                    };
+                };
+            };
+        };
+    };
+    getIncomplete: {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        requestBody?: never;
+        responses: {
+            /** @description OK */
+            200: {
+                headers: {
+                    [name: string]: unknown;
+                };
+                content: {
+                    "*/*": components["schemas"]["Document"][];
+                };
+            };
+        };
+    };
+    getNextIncomplete: {
+        parameters: {
+            query: {
+                excludeId: string;
+            };
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        requestBody?: never;
+        responses: {
+            /** @description OK */
+            200: {
+                headers: {
+                    [name: string]: unknown;
+                };
+                content: {
+                    "*/*": components["schemas"]["Document"];
+                };
+            };
+            /** @description No Content */
+            204: {
+                headers: {
+                    [name: string]: unknown;
+                };
+                content?: never;
+            };
+        };
+    };
     importStatus: {
         parameters: {
             query?: never;