feat(v4.0.0): Complete metadata/vector separation architecture with Azure support

This commit completes the core v4.0.0 architecture changes for billion-scale
performance with metadata/vector separation. NO RELEASE YET - remaining optimizations
and testing required before production release.

## Core v4.0.0 Architecture Changes

### Type System Updates
- Fixed all TypeScript compilation errors (zero errors achieved)
- Updated HNSWNoun/HNSWVerb to separate core fields from metadata
- Implemented HNSWNounWithMetadata/HNSWVerbWithMetadata for API boundaries
- Added required 'noun' field to NounMetadata for semantic structure
- Renamed verb.type to verb.verb for consistency

### Storage Adapter Updates
**All adapters updated for v4.0.0 two-file storage pattern:**
- memoryStorage: Proper metadata/vector separation
- fileSystemStorage: Two-file pattern with sharding
- opfsStorage: Browser persistent storage updated
- s3CompatibleStorage: AWS/MinIO/DigitalOcean support
- r2Storage: Cloudflare R2 optimization
- gcsStorage: Google Cloud with ADC support
- **azureBlobStorage: NEW - Full Azure Blob Storage support**

### Storage Features
- BaseStorage: Internal vs public method separation (_getNoun vs getNoun)
- Two-file storage: Vectors in one file, metadata in another
- Change tracking: getChangesSince return type updated
- Pagination: getNounsWithPagination returns WithMetadata types

### Azure Blob Storage Integration (NEW)
- Native @azure/storage-blob SDK integration
- Four authentication methods:
  * DefaultAzureCredential (Managed Identity) - recommended
  * Connection String - simplest setup
  * Account Name + Key - traditional auth
  * SAS Token - delegated access
- High-volume mode with write buffering
- Adaptive backpressure for throttling
- UUID-based sharding for billion-scale
- Full HNSW support with graph persistence

### Utility Updates
- EmbeddingManager: Updated to accept Record<string, unknown>
- LSMTree: Wrapped data in NounMetadata structure with 'noun' field
- EntityIdMapper: Fixed nested metadata.data structure access
- MetadataIndex: Fixed field type inference integration
- PeriodicCleanup: Updated for new metadata structure

### Core API Updates
- Brainy: Updated verb property access from v.type to v.verb
- ConfigAPI: Fixed NounMetadata access patterns
- DataAPI: Updated metadata handling

### Documentation Updates
- CREATING-AUGMENTATIONS.md: v4.0.0 breaking changes guide
- DEVELOPER-GUIDE.md: Migration checklist and examples
- COMPLETE-REFERENCE.md: v4.0.0 architecture improvements
- **finite-type-system.md: NEW - Revolutionary type system benefits**

### Build & Dependencies
- Zero TypeScript compilation errors
- Added @azure/storage-blob and @azure/identity
- 591 tests passing (23 timeout in long-running neural tests)

## What's NOT in This Release
This is a work-in-progress commit. Before v4.0.0 release we need:
- Storage adapter optimizations (batch operations, compression)
- Azure blob tier management (Hot/Cool/Archive)
- Cost optimization implementations
- Additional performance testing at billion-scale
- Migration guides for v3.x users

## Testing
- Clean build: ✅
- Type checking: ✅ (zero errors)
- Test suite: ✅ (591/614 passing, timeouts in neural tests only)

🔐 Generated with Claude Code
https://claude.com/claude-code

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

src/storage/storageFactory.ts

@@ -9,6 +9,7 @@ import { OPFSStorage } from './adapters/opfsStorage.js'
 import { S3CompatibleStorage } from './adapters/s3CompatibleStorage.js'
 import { R2Storage } from './adapters/r2Storage.js'
 import { GcsStorage } from './adapters/gcsStorage.js'
+import { AzureBlobStorage } from './adapters/azureBlobStorage.js'
 import { TypeAwareStorageAdapter } from './adapters/typeAwareStorageAdapter.js'
 // FileSystemStorage is dynamically imported to avoid issues in browser environments
 import { isBrowser } from '../utils/environment.js'
@@ -28,9 +29,10 @@ export interface StorageOptions {
    * - 'r2': Use Cloudflare R2 storage
    * - 'gcs': Use Google Cloud Storage (S3-compatible with HMAC keys)
    * - 'gcs-native': Use Google Cloud Storage (native SDK with ADC)
+   * - 'azure': Use Azure Blob Storage (native SDK with Managed Identity)
    * - 'type-aware': Use type-first storage adapter (wraps another adapter)
    */
-  type?: 'auto' | 'memory' | 'opfs' | 'filesystem' | 's3' | 'r2' | 'gcs' | 'gcs-native' | 'type-aware'
+  type?: 'auto' | 'memory' | 'opfs' | 'filesystem' | 's3' | 'r2' | 'gcs' | 'gcs-native' | 'azure' | 'type-aware'
 
   /**
    * Force the use of memory storage even if other storage types are available
@@ -177,6 +179,36 @@ export interface StorageOptions {
     secretAccessKey?: string
   }
 
+  /**
+   * Configuration for Azure Blob Storage (native SDK with Managed Identity)
+   */
+  azureStorage?: {
+    /**
+     * Azure container name
+     */
+    containerName: string
+
+    /**
+     * Azure Storage account name (for Managed Identity or SAS)
+     */
+    accountName?: string
+
+    /**
+     * Azure Storage account key (optional, uses Managed Identity if not provided)
+     */
+    accountKey?: string
+
+    /**
+     * Azure connection string (highest priority if provided)
+     */
+    connectionString?: string
+
+    /**
+     * SAS token (optional, alternative to account key)
+     */
+    sasToken?: string
+  }
+
   /**
    * Configuration for Type-Aware Storage (type-first architecture)
    * Wraps another storage adapter and adds type-first routing
@@ -473,6 +505,24 @@ export async function createStorage(
           return new MemoryStorage()
         }
 
+      case 'azure':
+        if (options.azureStorage) {
+          console.log('Using Azure Blob Storage (native SDK)')
+          return new AzureBlobStorage({
+            containerName: options.azureStorage.containerName,
+            accountName: options.azureStorage.accountName,
+            accountKey: options.azureStorage.accountKey,
+            connectionString: options.azureStorage.connectionString,
+            sasToken: options.azureStorage.sasToken,
+            cacheConfig: options.cacheConfig
+          })
+        } else {
+          console.warn(
+            'Azure storage configuration is missing, falling back to memory storage'
+          )
+          return new MemoryStorage()
+        }
+
       case 'type-aware': {
         console.log('Using Type-Aware Storage (type-first architecture)')
 
@@ -571,6 +621,19 @@ export async function createStorage(
     })
   }
 
+  // If Azure storage is specified, use it
+  if (options.azureStorage) {
+    console.log('Using Azure Blob Storage (native SDK)')
+    return new AzureBlobStorage({
+      containerName: options.azureStorage.containerName,
+      accountName: options.azureStorage.accountName,
+      accountKey: options.azureStorage.accountKey,
+      connectionString: options.azureStorage.connectionString,
+      sasToken: options.azureStorage.sasToken,
+      cacheConfig: options.cacheConfig
+    })
+  }
+
   // Auto-detect the best storage adapter based on the environment
   // First, check if we're in Node.js (prioritize for test environments)
   if (!isBrowser()) {
@@ -632,6 +695,7 @@ export {
   S3CompatibleStorage,
   R2Storage,
   GcsStorage,
+  AzureBlobStorage,
   TypeAwareStorageAdapter
 }