feat(execution): add ERC-1155 transfer support and test matrix

### Summary
Implement ERC-1155 support in execution engine.

### Why
ERC-1155 is in v1 scope and needed for heterogeneous assets.

### Scope
- Add single and batch ERC-1155 transfer handling
- Handle receiver behavior safely
- Add targeted tests

### Acceptance Criteria
- ERC-1155 transfers execute correctly
- Receiver/callback behavior tested