fix(portal): show Weight/DoB + Size Category in pet read view (GRO-2207)

Portal GET /api/portal/pets serializes weightKg→weight and dateOfBirth→
birthDate. The portal read view read the staff-shaped keys, so populated
pets rendered 'Unknown'. Size Category (petSizeCategory) was never shown
in any read tab.

- packages/types: add portal-shaped weight?/birthDate? alongside the
  existing staff-side weightKg/dateOfBirth (no rename — staff Clients
  pages still use weightKg/dateOfBirth).
- PetProfiles: header + Basic Info InfoRows read portal keys with a
  fallback to staff keys; add a Size Category InfoRow with a
  formatSizeCategory helper (extra_large → 'Extra Large').
- PetForm: pre-fill weight from portal weight key with weightKg fallback.
- Tests: PetProfiles.test.tsx (read view + formatter) and a PetForm
  pre-fill case.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/__tests__/PetForm.test.tsx

@@ -154,4 +154,12 @@ describe("PetForm", () => {
     expect(screen.getByText("Anxious")).toBeTruthy();
     expect(screen.getByText("Good with kids")).toBeTruthy();
   });
+
+  // ── Weight pre-fill from portal `weight` key (GRO-2207) ───────────────────────
+
+  it("pre-fills weight from the portal `weight` key when weightKg is absent", () => {
+    const portalPet: Pet = { ...BASE_PET, weightKg: null, weight: "12.50" };
+    render(<PetForm pet={portalPet} onSave={onSave} onCancel={onCancel} />);
+    expect(screen.getByDisplayValue(12.5)).toBeTruthy();
+  });
 });