Implement CE-WP-0009: wire umbrella to @citation-evidence/engine

Add link: dependency on citation-engine, retarget @shared/@engine aliases,
remove in-repo shared/engine copies. ADR-0002 accepted (option B).
172 tests, typecheck, and lint pass.

src/app/forms/capture-persistence.test.ts

@@ -4,7 +4,8 @@
 
 import { describe, expect, it } from "vitest";
 
-import type { SessionId } from "@shared/ids";
+import type { EvidenceLink } from "@shared/evidence-link";
+import type { EvidenceItemId, EvidenceLinkId, SessionId } from "@shared/ids";
 
 import {
   CAPTURE_STATE_VERSION,
@@ -47,17 +48,17 @@ describe("capture-persistence", () => {
       fieldValues: { summary: "Tenant owes arrears", deadline: "2026-12-15" },
       evidenceLinks: [
         {
-          id: "evlink_1",
-          evidenceItemId: "evi_1",
+          id: "evlink_1" as EvidenceLinkId,
+          evidenceItemId: "evi_1" as EvidenceItemId,
           targetType: "form-field",
           targetId: "summary",
           relation: "supports",
           status: "candidate",
           createdAt: "2026-06-08T00:00:00.000Z",
           updatedAt: "2026-06-08T00:00:00.000Z",
-        },
+        } satisfies EvidenceLink,
       ],
-    } as const;
+    };
 
     saveCaptureState(SESSION, withData, storage);
     const loaded = loadCaptureState(SESSION, storage);