test(analytics): pin the effective-range resolver's sex-split defaults

The resolver reads the profile's sex for the body-fat and pulse bands, and
nothing asserted it. A resolver that stopped reading the field, or read it and
defaulted to one side, passed the whole suite. Pin both recorded sides and the
neutral band that OTHER and an unanswered profile share.

src/lib/analytics/__tests__/effective-range.test.ts

@@ -90,6 +90,29 @@ describe("getEffectiveRange", () => {
   });
 });
 
+// The resolver narrows the stored three-value sex to the two a sex-split
+// reference table has rows for, and OTHER / "no answer" must land on the
+// neutral band rather than on either side. Nothing pinned that before, so a
+// resolver that quietly stopped reading the profile's sex — or read it and
+// picked a default side — went unnoticed.
+describe("sex-split defaults", () => {
+  const withGender = (gender: string | null) =>
+    getEffectiveRange("BODY_FAT", { ...baseProfile, gender }, null).range!;
+
+  it("gives each recorded side its own body-fat band", () => {
+    expect(withGender("MALE").greenMin).toBe(14);
+    expect(withGender("MALE").greenMax).toBe(24);
+    expect(withGender("FEMALE").greenMin).toBe(21);
+    expect(withGender("FEMALE").greenMax).toBe(31);
+  });
+
+  it("gives OTHER and an unanswered profile the same neutral band", () => {
+    const neutral = { greenMin: 17, greenMax: 27 };
+    expect(withGender("OTHER")).toMatchObject(neutral);
+    expect(withGender(null)).toMatchObject(neutral);
+  });
+});
+
 describe("getAllEffectiveRanges", () => {
   it("returns an entry for every metric", () => {
     const ranges = getAllEffectiveRanges(baseProfile, null);