fix: metadata explosion bug - 69K files reduced to ~1K

Critical fix for metadata indexing that was creating 60+ chunk files per entity.

Root cause: Vector embeddings (384-dimensional arrays) were being indexed in
metadata, causing each dimension to create a separate chunk file with numeric
field names ("0", "1", "2", etc.).

Changes:
- Modified extractIndexableFields() to exclude vector/embedding fields
- Added NEVER_INDEX set: ['vector', 'embedding', 'embeddings', 'connections']
- Added safety check to skip arrays > 10 elements
- Preserves small array indexing (tags, categories, roles)

Impact:
- Reduces metadata files from 69,429 → ~1,200 (58x reduction)
- Fixes server initialization hangs
- Fixes metadata batch loading stalling at batch 23
- Fixes VFS getDescendants() hanging with large datasets
- Fixes Graph View UI not loading

Test Results:
- 7/7 integration tests passing
- Verified: 6 chunk files for 10 entities (was 7,210 before fix)
- 611/622 unit tests passing

Files Modified:
- src/utils/metadataIndex.ts - Core fix
- src/coreTypes.ts - HNSWVerb type enforcement with VerbType enum
- src/storage/adapters/* - Include core relational fields in HNSWVerb
- src/storage/adapters/baseStorageAdapter.ts - Type enforcement (HNSWNoun, GraphVerb)
- tests/integration/metadata-vector-exclusion.test.ts - Comprehensive test coverage

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/storage/adapters/baseStorageAdapter.ts

@@ -3,7 +3,7 @@
  * Provides common functionality for all storage adapters, including statistics tracking
  */
 
-import { StatisticsData, StorageAdapter } from '../../coreTypes.js'
+import { StatisticsData, StorageAdapter, HNSWNoun, GraphVerb } from '../../coreTypes.js'
 import { extractFieldNamesFromJson, mapToStandardField } from '../../utils/fieldNameTracking.js'
 import { getGlobalMutex, cleanupMutexes } from '../../utils/mutex.js'
 
@@ -14,23 +14,23 @@ export abstract class BaseStorageAdapter implements StorageAdapter {
   // Abstract methods that must be implemented by subclasses
   abstract init(): Promise<void>
 
-  abstract saveNoun(noun: any): Promise<void>
+  abstract saveNoun(noun: HNSWNoun): Promise<void>
 
-  abstract getNoun(id: string): Promise<any | null>
+  abstract getNoun(id: string): Promise<HNSWNoun | null>
 
-  abstract getNounsByNounType(nounType: string): Promise<any[]>
+  abstract getNounsByNounType(nounType: string): Promise<HNSWNoun[]>
 
   abstract deleteNoun(id: string): Promise<void>
 
-  abstract saveVerb(verb: any): Promise<void>
+  abstract saveVerb(verb: GraphVerb): Promise<void>
 
-  abstract getVerb(id: string): Promise<any | null>
+  abstract getVerb(id: string): Promise<GraphVerb | null>
 
-  abstract getVerbsBySource(sourceId: string): Promise<any[]>
+  abstract getVerbsBySource(sourceId: string): Promise<GraphVerb[]>
 
-  abstract getVerbsByTarget(targetId: string): Promise<any[]>
+  abstract getVerbsByTarget(targetId: string): Promise<GraphVerb[]>
 
-  abstract getVerbsByType(type: string): Promise<any[]>
+  abstract getVerbsByType(type: string): Promise<GraphVerb[]>
 
   abstract deleteVerb(id: string): Promise<void>
 
@@ -98,7 +98,7 @@ export abstract class BaseStorageAdapter implements StorageAdapter {
       metadata?: Record<string, any>
     }
   }): Promise<{
-    items: any[]
+    items: HNSWNoun[]
     totalCount?: number
     hasMore: boolean
     nextCursor?: string
@@ -123,7 +123,7 @@ export abstract class BaseStorageAdapter implements StorageAdapter {
       metadata?: Record<string, any>
     }
   }): Promise<{
-    items: any[]
+    items: GraphVerb[]
     totalCount?: number
     hasMore: boolean
     nextCursor?: string
@@ -144,7 +144,7 @@ export abstract class BaseStorageAdapter implements StorageAdapter {
       metadata?: Record<string, any>
     }
   }): Promise<{
-    items: any[]
+    items: HNSWNoun[]
     totalCount?: number
     hasMore: boolean
     nextCursor?: string
@@ -167,7 +167,7 @@ export abstract class BaseStorageAdapter implements StorageAdapter {
       metadata?: Record<string, any>
     }
   }): Promise<{
-    items: any[]
+    items: GraphVerb[]
     totalCount?: number
     hasMore: boolean
     nextCursor?: string