feat(admin): normalize Persian/Arabic digits in every numeric field

Users typing on a Persian keyboard produced two distinct failures. Fields with
type="number" silently returned an empty string — the browser rejects Persian
digits, so the value was lost and saved as empty or zero. Text fields passed the
Persian characters straight through to the database, where a mobile stored as
۰۹۱۲… never matches 09… again. The secretary form hit the second case with no
validation at all.

Frontend:
- Adds digitsOnly() and the national-code schemas to lib/utils, plus lib/forms
  with numericField()/latinDigitsField() wrappers for React Hook Form fields.
- Converts every type="number" input to type="text" inputMode="numeric" with
  digit normalization; none remain. Fields that legitimately carry non-digits
  (sheba, landline) only get the digits translated, keeping IR and separators.
- Points the patient national-code and mobile schemas at the shared normalizing
  schemas, which accept Persian input instead of rejecting it.
- Drops two duplicate local digit converters in favour of the shared helper.

Backend:
- Adds NumericFieldNormalizerSubscriber, translating digits in whitelisted
  numeric keys of JSON request bodies under /api/v1/ before controllers run, so
  nobat724_front and clinic-pro-tauri are covered too. Translation only — no
  characters are stripped, non-string values and other keys are untouched.

Three component tests asserted on role="spinbutton" and numeric input values;
both are properties of type="number", so they were updated to match the new
text inputs.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/api/secretary.md

@@ -79,9 +79,9 @@ Create a secretary for a doctor.
 | --------------- | ------------- | -------- | -------------------------------------------- |
 | `doctor_uuid`   | string (UUID) | ✅\*      | Single doctor to assign (legacy/doctor flow) |
 | `doctor_uuids`  | string[] (UUID) | ✅\*    | **Clinic only** — assign one secretary to several clinic doctors at once. When present (non-empty) and caller is `ROLE_CLINIC`, this multi-doctor path is used instead of `doctor_uuid` |
-| `mobile_number` | string        | ✅       | Secretary's login mobile                     |
+| `mobile_number` | string        | ✅       | Secretary's login mobile. Persian/Arabic digits are accepted and normalized server-side — see [README → Persian digit normalization](README.md#persian-digit-normalization-global) |
 | `name`          | string        | ❌       | Full name (نام + نام خانوادگی) → `user_name` |
-| `national_code` | string        | ❌       | کد ملی منشی (nullable)                       |
+| `national_code` | string        | ❌       | کد ملی منشی (nullable). Persian/Arabic digits accepted and normalized |
 | `address`       | string        | ❌       | آدرس منشی (nullable)                          |
 | `password`      | string        | ❌       | Initial password (auto-generated if omitted) |
 | `permissions`   | object        | ❌       | Permission set (see structure below)         |