Introduce a dedicated use case for starting the sandbox runtime while keeping launch execution centralized.

Docker sandbox improvements:
- Switch from file mounting to directory mounting for policy file
  (more reliable with Docker Desktop VirtioFS)
- Add retry-with-backoff for Docker mount race conditions
- Remove heavyweight Alpine container polling approach

Setup wizard improvements:
- Launch comprehensive setup wizard directly when no config exists
- Remove simple text prompt in favor of full wizard experience

Workspace picker improvements:
- Add CwdContext pattern for current directory detection
- Move project marker detection to services layer
- Fix "Current directory" option appearing in workspace picker

Architecture improvements:
- Add typed config models (NormalizedOrgConfig, etc.)
- Add ConfigStore port and LocalConfigStore adapter
- Add support bundle use case with DoctorRunner port
- Add flow_types.py for wizard state helpers
- Add core/enums.py for domain enums
- Improve doctor module to use SeverityLevel enum

Test updates:
- Update Docker policy mount tests for directory mounting
- Add config normalization tests
- Add wizard state machine tests

Remove maintainability-review.md and progress.txt files that were used during
development and should not be part of the codebase.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

- Add reset_plugin_caches() to clear Claude Code's cached marketplace paths
  when switching between workspaces (main repo vs worktrees)
- Update reset_global_settings() to clear both settings.json and plugin caches
  (known_marketplaces.json, installed_plugins.json) preventing "Plugin not found
  in marketplace" errors caused by stale paths from previous sessions
- Fix "Switch team" action in Quick Resume to navigate to team picker instead
  of workspace source picker by explicitly setting step to TEAM_SELECTION