Sriram Naidu Thota 38c96bc53e fix: validate base64 image data before API submission
Adds explicit base64 format validation in sanitizeContentBlocksImages()
to prevent invalid image data from being sent to the Anthropic API.

The Problem:
- Node's Buffer.from(str, "base64") silently ignores invalid characters
- Invalid base64 passes local validation but fails at Anthropic's stricter API
- Once corrupted data persists in session history, every API call fails

The Fix:
- Add validateAndNormalizeBase64() function that:
  - Strips data URL prefixes (e.g., "data:image/png;base64,...")
  - Validates base64 character set with regex
  - Checks for valid padding (0-2 '=' chars)
  - Validates length is proper for base64 encoding
- Invalid images are replaced with descriptive text blocks
- Prevents permanent session corruption

Tests:
- Rejects invalid base64 characters
- Strips data URL prefixes correctly
- Rejects invalid padding
- Rejects invalid length
- Handles empty data gracefully

Closes #18212

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2026-02-16 23:53:54 +01:00
..
2026-01-20 10:51:25 +00:00
2026-01-19 00:34:26 +00:00
2026-01-30 03:16:21 +01:00
2026-01-14 15:02:19 +00:00
2026-02-09 18:56:58 -08:00