Reorganize the store into a modular directory structure with barrel exports. File moves only - no logic changes.

Acceptance Criteria:

• Create wizard/ directory with subdomain directories: e.g. core/, targets/ etc
• Create blueprints/, env/, cloudProviderConfig/ module directories
• Create api/service/ and api/cockpit/ directories for RTK Query APIs
• Selectors extracted into selectors.ts files per module
• All imports across the codebase are updated
• store/index.ts updated to use new barrel imports
• No runtime behavior changes
• All tests pass
• Application builds successfully