Fix QA review 2719: optional coatType/petSizeCategory, CoatType union, null guards

- Make coatType and petSizeCategory optional on Pet (?:) — they may not be set
- Remove "single" and "short" from COAT_TYPES (not in CoatType union)
- Use { name: "Add" } instead of /add/i to target the + button specifically
- Add optional chaining to puppyCutSpans[0]?.closest() (noUncheckedIndexedAccess)
- Add optional chaining to petsData[0]?.id ?? "" in PetProfiles

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

packages/types/src/index.ts

@@ -39,8 +39,8 @@ export interface Pet {
   cutStyle: string | null;
   shampooPreference: string | null;
   specialCareNotes: string | null;
-  coatType: string | null;
-  petSizeCategory: string | null;
+  coatType?: string | null;
+  petSizeCategory?: string | null;
   preferredCuts: string[];
   medicalAlerts: MedicalAlert[];
   temperamentScore?: number;