docs: add V2 API status documentation

Add comprehensive documentation explaining the current state of
the v2 API implementation, including:
- Clear warning that v2 API doesn't exist in ChromaDB yet
- Known issues and limitations
- CI/CD workflow documentation
- Recommendations for users
- Future work needed when v2 API is released

This helps set proper expectations for anyone looking at the v2
implementation and explains why tests are currently failing.

Co-Authored-By: Claude <[email protected]>

Author: tazarov

V2_API_STATUS.md

@@ -0,0 +1,67 @@
+# V2 API Implementation Status
+
+## Overview
+This directory contains an experimental implementation of the ChromaDB v2 API client.
+
+**⚠️ Important:** The v2 API does not yet exist in ChromaDB. This implementation is based on anticipated v2 API design and is provided for experimental/preview purposes only.
+
+## Current Status
+
+### What's Implemented
+- Basic client structure (`ServerClient`, `CloudClient`)
+- Authentication providers (Basic, Token, ChromaToken)
+- Model classes for v2 operations
+- Collection operations interface
+- Query builder pattern
+
+### Known Issues
+1. **API Endpoints:** Currently modified to use `/api/v1` endpoints as a temporary workaround
+2. **Tenant/Database Support:** v2 expects multi-tenancy which v1 doesn't support
+3. **Response Models:** Field names and structure differ between v1 and v2
+4. **Tests:** Most tests will fail against current ChromaDB versions
+
+## CI/CD Configuration
+
+The repository includes GitHub Actions workflows for v2 API testing:
+- `.github/workflows/v2-api-tests.yml` - Main test workflow
+- `.github/workflows/v2-api-pr-validation.yml` - PR validation
+- `.github/workflows/v2-api-nightly.yml` - Nightly compatibility tests
+- `.github/workflows/v2-api-release.yml` - Release workflow
+
+**Note:** These workflows are currently expected to fail until ChromaDB implements the actual v2 API.
+
+## Usage
+
+### For Experimental Development Only
+```java
+// This code will not work with current ChromaDB versions
+ServerClient client = ServerClient.builder()
+    .baseUrl("http://localhost:8000")
+    .auth(AuthProvider.none())
+    .build();
+
+// Operations will fail or behave unexpectedly
+Collection collection = client.createCollection("my_collection");
+```
+
+## Recommendations
+
+1. **Do not use in production** - This is experimental code
+2. **Use v1 Client** - For all actual ChromaDB operations, use the stable v1 client in `tech.amikos.chromadb.Client`
+3. **Monitor ChromaDB releases** - Watch for official v2 API announcements
+
+## Future Work
+
+When ChromaDB releases the actual v2 API:
+1. Update all endpoints from the temporary v1 paths
+2. Align model classes with actual v2 response structures
+3. Implement proper tenant/database handling
+4. Update tests to match real v2 behavior
+5. Remove this warning documentation
+
+## Contributing
+
+If you're interested in the v2 API development:
+- Check ChromaDB's official repository for v2 API proposals
+- Test against ChromaDB development branches if available
+- Report issues specific to v2 API design (not current failures)