DRY pass #2, batch 8: the Shared-with-me facet is tested once (#5372)

sharing.test.ts round-tripped shared=with_me, which facets.test.ts already
does with every facet; its unknown-value case moves there.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/notes/facets.test.ts

@@ -21,4 +21,8 @@ describe("the board's filter URL", () => {
     expect(facets).toEqual({});
     expect(facetCount(facets)).toBe(0);
   });
+
+  it("ignores a shared value it doesn't know", () => {
+    expect(facetsFromQuery({ shared: "by_me" })).toEqual({});
+  });
 });

frontend/src/notes/sharing.test.ts

@@ -1,7 +1,6 @@
 import { describe, expect, it } from "vitest";
 
 import { canEditText, isOwnNote } from "./sharing";
-import { facetCount, facetsFromQuery, facetsToQuery } from "./facets";
 import type { Note } from "../stores/notes";
 
 const note = (extra: Partial<Note>): Note => ({ ...({} as Note), ...extra });
@@ -21,16 +20,3 @@ describe("how a note is held", () => {
     expect(canEditText(note({ permission: "view" }))).toBe(false);
   });
 });
-
-describe("the Shared with me facet", () => {
-  it("round-trips through the URL and counts as one filter", () => {
-    const facets = facetsFromQuery({ shared: "with_me" });
-    expect(facets).toEqual({ shared: "with_me" });
-    expect(facetsToQuery(facets)).toEqual({ shared: "with_me" });
-    expect(facetCount(facets)).toBe(1);
-  });
-
-  it("ignores a value it doesn't know", () => {
-    expect(facetsFromQuery({ shared: "by_me" })).toEqual({});
-  });
-});