[Bug report] Security: outdated libpng (1.6.38) and libtiff (≤4.7.0) bundled in MLKitTextRecognitionCommon (iOS) — CVE-2025-64720, CVE-2025-65018, CVE-2025-9900

### Summary
The iOS `MLKitTextRecognitionCommon.framework` statically bundles outdated copies of
libpng and libtiff that are affected by recently disclosed CVEs. Because these libraries
are compiled into Google's pre-built binary, downstream SDKs and apps cannot patch them
and are flagged by enterprise security scanners.

### Affected SDK
- Pod: `GoogleMLKit/TextRecognition` (verified across versions 6.0.0 through 9.0.0)
- Framework: `MLKitTextRecognitionCommon.framework`
- Platform: iOS

### Bundled library versions (verified via `strings` on the published pod binary)
| Library | Version in framework | Affected CVEs | Fixed upstream in |
|---|---|---|---|
| libpng | 1.6.38 (Sep 14, 2022) | CVE-2025-64720, CVE-2025-65018 | libpng 1.6.51 (Nov 22, 2025) |
| libtiff | 4.6.0–4.7.0 (varies by Common version) | CVE-2025-9900 | libtiff 4.7.1 |
| libjpeg-turbo | 2.1.5.1 | (informational, not flagged) | — |

### How to reproduce
```bash
# After `pod install` of GoogleMLKit/TextRecognition:
BIN=Pods/MLKitTextRecognitionCommon/Frameworks/MLKitTextRecognitionCommon.framework/MLKitTextRecognitionCommon
strings "$BIN" | grep -iE "libpng version|LIBTIFF, Version"
# Output includes:
# libpng version 1.6.38
# LIBTIFF, Version 4.6.0 (or 4.7.0 on newer Common releases)