✨[Feat] Sprint 1 Bounded Binary Core and Format Detection - #2

Summary

• add centralized safe-integer range validation with subtraction-based capacity checks
• add a read-only ByteReader for u8, endian-aware u16/u32, bounded subarray views, and allocation-free signature matching
• normalize ArrayBuffer and exact Uint8Array views without copying or widening caller ranges
• detect JPEG from FF D8, PNG from its complete eight-byte signature, and WebP from RIFF....WEBP
• integrate maxInputBytes enforcement and format detection into inspectMetadata
• mark reports as format-only so empty entries never claim metadata is absent
• preserve deterministic NOT_IMPLEMENTED behavior for cleaning and verification

Tests

• 7 test files, 68 tests passed
• valid and invalid byte-reader boundaries, including unsigned u32 maximum
• sliced Uint8Array backing-buffer regression coverage
• JPEG, PNG, WebP, truncated-signature, and arbitrary RIFF cases
• deterministic malformed inputs, input limits, input preservation, and repeatability

Deferred

No segment or chunk traversal, RIFF-size validation, CRC checking, EXIF/TIFF/GPS/XMP/IPTC/ICC decoding, metadata cleaning, rewriting, decompression, image decoding, fuzzing, UI, Rust, or WASM is included.

Validation

• npm run format:check — passed
• npm run lint — passed
• npm run typecheck — passed
• npm test — 7 files, 68 tests passed
• npm run build — ESM, source map, and declarations built
• npm audit — 0 vulnerabilities
• npm ls --omit=dev --depth=0 — 0 runtime dependencies
• npm pack --dry-run — expected 7-file, 8.1 kB package payload

Security review

All DataView reads follow project-owned bounds validation. Range capacity is checked with subtraction before any validated addition or direct byte indexing. Input normalization makes no whole-input copies, inspector code performs no writes, and source code introduces no network, filesystem, DOM, or Node-runtime dependency.