feat: Add Pinecone vector store backend support

[Oxazolidinone]

No description provided.

[willingWill17]

Please resolve your bug

[Oxazolidinone]

Implement Pinecone Vector Storage Backend for Cipher

Summary

This PR adds a complete Pinecone vector storage backend implementation to Cipher, enabling production-ready vector search capabilities using Pinecone's cloud-native vector database.

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Features Implemented

1. Pinecone Backend Implementation

• Full CRUD operations: insert, search, update, delete
• Batch operations with configurable batch sizes
• Namespace support for data isolation
• Comprehensive error handling and retry logic
• Metadata filtering and search capabilities

2. Configuration Support

VECTOR_STORE_TYPE=pinecone
VECTOR_STORE_API_KEY=your-api-key
PINECONE_NAMESPACE=default

3. Schema Validation

const PineconeBackendSchema = BaseVectorStoreSchema.extend({
  type: z.literal('pinecone'),
  apiKey: z.string().describe('Pinecone API key'),
  indexName: z.string().describe('Pinecone index name'),
  namespace: z.string().default(DEFAULTS.PINECONE_NAMESPACE).optional(),
  dimension: z.number().positive().default(DEFAULTS.DIMENSION).optional(),
});

4. Key Features

• Namespace Isolation: Multiple environments/projects supported
• Batch Processing: Optimized for large-scale operations
• Metadata Support: Rich filtering and search capabilities
• Error Handling: Retry logic and structured error management
• Type Safety: Full TypeScript support

5. Integration Points

• Added to discriminated union in BackendConfigSchema
• Environment variable support in 'env.ts`
• Factory pattern integration for seamless backend switching
  Constants defined for default values

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Files Modified

• src/core/vector_storage/backend/pinecone.ts
• src/core/vector_storage/config.ts
• src/core/vector_storage/constants.ts
• src/core/vector_storage/factory.ts
• src/core/env.ts
• src/core/vector_storage/backend/types.ts