anya-core 1.2.0

# Bitcoin Improvement Proposals (BIP) Implementation Index
[AIR-3][AIS-3][BPC-3][AIT-3][RES-3]

This document provides an index of all Bitcoin Improvement Proposals (BIPs) implemented in the Anya-Core project, following the Bitcoin Development Framework v2.5.

## Implemented BIPs

| BIP | Title | Implementation | Test Coverage | Audit Status |
|-----|-------|----------------|--------------|--------------|
| 341 | Taproot | `core/src/bip/bip341.rs` | Partial | In Progress |
| 342 | Tapscript | `core/src/bip/bip342.rs` | Partial | In Progress |
| 174 | PSBT | `src/bitcoin/protocol/psbt.rs` | Pending | Not Started |
| 370 | BIPScript | `src/bitcoin/protocol/script.rs` | Partial | Not Started |

## Implementation Details

### BIP-341 (Taproot)

Implementation of the Taproot proposal, which introduces a new SegWit version 1 output type that can be spent using either a key path or by satisfying a script path.

**Features Implemented:**
- Taproot Merkle Tree construction
- Taproot spend validation
- Taproot output generation
- Key path spending
- Script path spending

**Location:** `core/src/bip/bip341.rs`

### BIP-342 (Tapscript)

Implementation of the Tapscript, which defines the semantics of the leaf version and the script execution context for spending Taproot outputs along the script path.

**Features Implemented:**
- Leaf version handling
- Tapscript execution
- Signature validation with specified rules
- Size limits and resource constraints

**Location:** `core/src/bip/bip342.rs`

## Implementation Priorities

The following BIPs are prioritized for upcoming implementation:

1. BIP-174 (PSBT) - Partially Signed Bitcoin Transactions
2. BIP-370 (PSBT v2) - Enhanced version of PSBT
3. BIP-340 (Schnorr Signatures) - Foundational for later enhancements

## Compliance Requirements

All BIP implementations must:
- Pass the standard Bitcoin test vectors
- Follow the hexagonal architecture pattern
- Include comprehensive security checks
- Be thoroughly documented

## Testing Strategy

1. **Unit Tests:** Direct validation of implementation against test vectors
2. **Integration Tests:** Interaction between multiple BIP implementations
3. **Security Tests:** Fuzz testing and edge case exploration
4. **Regression Tests:** Ensure compatibility with Bitcoin Core

## Audit Status

Regular security audits are conducted on all BIP implementations, with results documented in `security/audit/bip_audit_reports.md`.