Add IP Vault: Cryptographic proof-of-origin system

Implements a complete vertical slice of the IP Vault feature for BlackRoad OS,
providing cryptographic timestamping and evidence generation for ideas and
intellectual property.

## Components Added

### Agent Layer
- **VaultAgent** (`agents/categories/security/vault_agent.py`):
  - Deterministic text canonicalization
  - Multi-hash generation (SHA-256, SHA-512, Keccak-256)
  - LEO (Ledger Evidence Object) construction
  - Verification text generation
  - Blockchain anchoring preparation

### Backend API
- **Models** (`backend/app/models/leo.py`):
  - LEO: Stores cryptographic hashes and metadata
  - AnchorEvent: Audit trail for blockchain anchoring

- **Schemas** (`backend/app/schemas/leo.py`):
  - LEOCreate, LEOResponse, LEODetail, LEOList
  - AnchorRequest, AnchorEventResponse

- **Router** (`backend/app/routers/ip_vault.py`):
  - POST /api/vault/leos - Create new LEO
  - GET /api/vault/leos - List LEOs (paginated)
  - GET /api/vault/leos/{id} - Get LEO details
  - POST /api/vault/leos/{id}/anchor - Initiate anchoring (stub)
  - GET /api/vault/leos/{id}/events - Get anchor events

### Frontend
- **API Client** (`backend/static/js/api-client.js`):
  - createLEO(), getLEOs(), getLEO()
  - anchorLEO(), getLEOEvents()

- **App** (`backend/static/js/apps.js`):
  - loadIPVault() - Load and display LEOs
  - vaultIdea() - Create new LEO from form
  - viewLEO() - Show detailed LEO modal with verification

- **UI** (`backend/static/index.html`):
  - Desktop icon (🔐 IP Vault)
  - Window with form and list view
  - Start menu integration

## Features

- **Deterministic canonicalization**: Ensures reproducible hashing
- **Multi-hash support**: SHA-256, SHA-512, Keccak-256 (Ethereum-compatible)
- **Verification instructions**: Auto-generated proof-of-authenticity text
- **Blockchain-ready**: Prepared for Bitcoin, Litecoin, Ethereum anchoring
- **Clean separation**: Agent logic, API, database, frontend all decoupled

## Testing

- Python syntax validated for all new files
- JavaScript syntax validated
- VaultAgent tested end-to-end with sample idea
- All hashes computed successfully

## Next Steps

- Implement actual blockchain anchoring
- Add RoadChain integration
- Export LEOs as legal-grade PDFs
- Add user authentication to LEO creation

backend/app/schemas/leo.py

@@ -0,0 +1,72 @@
+"""LEO (Ledger Evidence Object) schemas"""
+from pydantic import BaseModel, Field
+from typing import Optional, Dict, Any
+from datetime import datetime
+
+
+class LEOCreate(BaseModel):
+    """LEO creation schema"""
+    idea: str = Field(..., min_length=1, description="Raw idea text to vault")
+    author: str = Field(default="Alexa", description="Author of the idea")
+    title: Optional[str] = Field(None, max_length=500, description="Optional title for the idea")
+
+
+class LEOResponse(BaseModel):
+    """LEO response schema"""
+    id: str
+    author: str
+    title: Optional[str]
+    sha256: str
+    sha512: str
+    keccak256: str
+    canonical_size: int
+    anchor_status: str
+    anchor_txid: Optional[str]
+    anchor_chain: Optional[str]
+    anchor_block_height: Optional[int]
+    anchored_at: Optional[datetime]
+    created_at: datetime
+    updated_at: Optional[datetime]
+
+    class Config:
+        from_attributes = True
+
+
+class LEODetail(LEOResponse):
+    """
+    Detailed LEO response with verification and anchoring info
+    """
+    verification_text: str
+    anchoring_options: Dict[str, Any]
+
+
+class LEOList(BaseModel):
+    """Paginated LEO list response"""
+    leos: list[LEOResponse]
+    total: int
+    page: int
+    per_page: int
+
+
+class AnchorRequest(BaseModel):
+    """Blockchain anchor request"""
+    chain: str = Field(
+        default="bitcoin",
+        description="Target blockchain (bitcoin, litecoin, ethereum)"
+    )
+
+
+class AnchorEventResponse(BaseModel):
+    """Anchor event response"""
+    id: int
+    leo_id: str
+    event_type: str
+    chain: Optional[str]
+    txid: Optional[str]
+    block_height: Optional[int]
+    status: str
+    error_message: Optional[str]
+    created_at: datetime
+
+    class Config:
+        from_attributes = True