Fix ArrayIndexOutOfBoundsException in FileTypeDetector and TypeCheckers

[AndreCatarino]

Problem

Fixes java.lang.ArrayIndexOutOfBoundsException in FileTypeDetector.detectFileType() and related TypeChecker implementations when processing truncated or incomplete input streams.

Root Cause: TypeCheckers (QuickTimeTypeChecker, RiffTypeChecker, MpegAudioTypeChecker) directly access byte array indices without verifying sufficient data is available.

Solution

• FileTypeDetector: Added bounds checking before calling TypeCheckers - only invoke when sufficient bytes are available
• QuickTimeTypeChecker: Added array length validation before accessing indices 4-11
• RiffTypeChecker: Added bounds check before creating strings from byte arrays
• MpegAudioTypeChecker: Added validation before accessing indices 0-2

Changes Made

• Enhanced FileTypeDetector.detectFileType() with offset >= checker.getByteCount() validation
• Added bytes.length < getByteCount() checks in all TypeChecker implementations
• Created FileTypeDetectorTest with 11 test scenarios

Testing

• Empty streams: Returns FileType.Unknown instead of crashing
• Partial data: Handles truncated headers gracefully (e.g., 8 bytes when 12 needed)
• Valid headers: Continues to work correctly for complete files
• Edge cases: MP3, QuickTime, RIFF formats with insufficient data

Impact

• Prevents crashes when analyzing corrupted, truncated, or malicious files
• Maintains backward compatibility - valid files continue to be detected correctly