Add set_workspace_provider() injection point so the cloud MCP server can
list workspaces by querying its own database directly, instead of making
an HTTP round-trip to the control-plane API with credentials it doesn't have.
🔧 Mirrors the existing set_client_factory() pattern in async_client.py
🧪 Adds 3 tests for provider injection, fallback, and context caching
🩹 Updates build_context test assertions for v0.18 backward compat fields
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Signed-off-by: phernandez <paul@basicmachines.co>
phernandez