Why

This is Phase 1 of the multi-project feature, extracting shared helper functions that both Server A (env-var mode) and Server B (multi-project mode) will use. This extraction is the blocking dependency for all subsequent phases.

What

• New src/dbt_mcp/project/ module with extracted helpers:

  • environment_resolver.py — resolve_environments() (pure logic) and get_environments_for_project() (API + resolution)
  • project_resolver.py — get_all_accounts() and get_all_projects_for_account()

• Refactored config providers (config_providers.py):

  • Each provider now has only get_config() (existing, unchanged behavior) and a _build_config() static method
  • Removed get_config_for_project(project_id) from all four providers — env resolution belongs in tool functions, not providers, keeping providers stateless
  • Tools in phases 3-6 will call get_environments_for_project() directly at call-time and pass the resolved environment ID to the provider's _build_config() or construct the config override inline

• Refactored fastapi_app.py:

  • Replaced inline account/project/environment functions with calls to the new extracted helpers
  • Replaced inline environment resolution logic with resolve_environments()
  • No behavior change

• Added DBT_MCP_MULTI_PROJECT_ENABLED env var check in main.py:

  • When set to true/1/yes, raises NotImplementedError (stub for Server B, implemented in Phase 7)
  • When absent/false, existing behavior unchanged (Server A)

• Updated existing pagination tests to reference new module paths

Notes

• All 451 unit tests pass
• task check passes (lint, format, mypy)
• No behavior change for existing Server A mode

Drafted by Claude Sonnet 4.6 under the direction of @DevonFulcher