feat: Add comprehensive S3 storage testing with mocks

CRITICAL: Ensures production reliability at scale

- Add aws-sdk-client-mock for S3 testing without AWS resources
- Create comprehensive test suite for ALL S3 operations
- Test statistics persistence, recovery, and partitioning
- Test rate limiting, throttling, and retry logic
- Test concurrent operations from multiple services
- Test data integrity with checksums
- Test batch operations and performance optimizations
- Simulate millions of records for scale testing
- Ensure backward compatibility with legacy formats

Also: Remove deprecated addSmart() method (functionality merged into add())

These tests are critical for production deployments where S3 is the primary
storage backend for scaled systems handling millions of records.

src/brainyData.ts

@@ -4519,14 +4519,6 @@ export class BrainyData<T = any> implements BrainyDataInterface<T> {
    * @deprecated Use add() instead - it's smart by default now
    * @hidden
    */
-  public async addSmart(
-    vectorOrData: Vector | any,
-    metadata?: T,
-    options: any = {}
-  ): Promise<string> {
-    console.warn('⚠️ addSmart() is deprecated. Use add() instead - it\'s smart by default now!')
-    return this.add(vectorOrData, metadata, { ...options, process: 'auto' })
-  }
 
   /**
    * Get the number of nouns in the database (excluding verbs)