## Outcome

**The prior `CHANGES REQUIRED` was an Important, release-blocking medical-data-integrity finding:** the former shared pattern used Python `\d`, which accepts Unicode decimal digits—not only ASCII `0–9`.

### Exact finding

- **Severity:** Important
- **Location:** `scripts/health/dashboard_v5/lab_registry.py:6`
- **Former unsafe form:**  
  ```python
  re.compile(r"^[+-]?\d+(?:[.,]\d+)?$")
  ```
- **Shared enforcement points:**
  - Provider import: `scripts/health/dashboard_v5/data_provider.py:15`
  - Provider check: `data_provider.py:228`
  - Contract import: `scripts/health/dashboard_v5/contracts.py:11`
  - Contract check: `contracts.py:213`
- **Consequence:** Arabic-Indic or full-width digits could pass both the provider and independent bundle trust boundary and then be displayed verbatim as an “original verified” result at `scripts/health/assets/health-assets/dashboard-v5.js:350`.

Minimal reproducer for the old pattern:

```python
import re

old = re.compile(r"^[+-]?\d+(?:[.,]\d+)?$")

assert old.fullmatch("١٢")   # Arabic-Indic digits: accepted
assert old.fullmatch("１２")  # Full-width digits: accepted
```

That violates the exact-number contract: downstream code and reviewers cannot safely assume an accepted value has the canonical ASCII representation expected for a verified laboratory number.

### Expected safe behavior

Accept only canonical ASCII forms such as:

```text
12
+12
-0.5
12,5
```

Reject Unicode numerals, censored values, exponent notation, and non-finite tokens:

```text
١٢
１２
<5
1e3
NaN
```

### Smallest safe fix

The current tree already contains the smallest fix:

```python
EXACT_LAB_NUMBER = re.compile(r"^[+-]?[0-9]+(?:[.,][0-9]+)?$")
```

at `lab_registry.py:6`. Using the old expression with `re.ASCII` would also be safe.

Current regression coverage is at `tests/test_health_dashboard_v5.py:260-268`, including Arabic-Indic and full-width digits. Reference bounds are now checked with the same exact-number pattern at `contracts.py:205-210`; provenance and canonical parameter/unit checks remain at `contracts.py:215-218`.

## Current focused status

- **No remaining release blocker found in this focused `EXACT_LAB_NUMBER` surface.**
- Synthetic runtime probes confirmed:
  - ASCII `"12"` accepted.
  - Arabic-Indic `"١٢"` rejected.
  - Full-width `"１２"` rejected.
  - Canonical-schema numeric zero is stored as text `"0"` and preserved by the provider.
- Imports are healthy for `lab_registry`, `contracts`, and `data_provider`.
- Tests:
  - **126 Python tests passed**
  - **19 focused Dashboard-v5 tests passed**
  - **13 Playwright tests passed** against a synthetic-only dashboard
  - `git diff --check` passed
- Initial browser attempt used an incorrect generic HTTP content type and triggered downloads; rerunning with the correct `text/html` fixture server passed all 13 tests.
- **Files modified or created by me:** none. Temporary synthetic test files and browser artifacts were removed; no production data was accessed.