feat: multi-type substitution (int/uint/int64/bool/float32) + type classification

Classify(fieldInfo): encoder identity = *( *(fieldInfo+0x38) + 0x30 ) compared
against known encode fns (EncodeInt32 0x3c8e70 signed, EncodeUInt32 0x3c8e90
unsigned, EncodeBool 0x3c4c00, EncodeFloat32 0x3ce8e0). Per-type emit: signed
zigzag-varint, unsigned raw-varint (same VarintWriter, rsi 64-bit covers 32/64),
bool 1-bit + float32 32-bit via a canonical WriteUBitLong reimpl. Unsupported
encoder -> passthrough (never writes wrong-type bits). 3 identity-only gamedata
sigs added (never called, comparison only). Also fixed build.sh .asset->.assets
typo (stale-gamedata root cause). Build 0/0.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>