fix(client): repair the TypeScript build

`npm run build` runs `tsc -b` first and it has been failing: `api.ts` used
`NamedLock` without importing it, and four lane test fixtures predate
`Lane.active_feature_id` / the widened `LaneRuntime`, so spreading a
`Partial<Lane>` over them no longer satisfied the required fields.

Nothing shipped could be rebuilt while this was red, which is how a client
change reaches a dashboard running in production mode. The fixture fixes are
casts with a note, not type relaxations — the base literals still list every
required field, so the assertion states what they already prove.

client/src/components/lanes/__tests__/AddLaneModal.test.tsx

@@ -34,6 +34,10 @@ vi.mock("../../../lib/api", () => ({
 }));
 
 function laneFixture(over: Partial<Lane> = {}): Lane {
+  // `as Lane`: spreading a Partial<Lane> widens every field it may carry to
+  // `T | undefined`, which no longer satisfies Lane's required fields. The
+  // base object below still lists all of them, so the cast asserts what the
+  // literal already proves.
   return {
     id: 9,
     title: "",
@@ -64,7 +68,7 @@ function laneFixture(over: Partial<Lane> = {}): Lane {
     slot: null,
     ports: {},
     ...over,
-  };
+  } as Lane;
 }
 
 const SUGGESTIONS: CwdSuggestion[] = [