Improve Initiative board management

[Cyber-preacher]

Summary

• keep all five Initiative board columns visible before cards exist
• move board-card creation to a dedicated route
• add confirmed card deletion for Initiative admins and stewards
• centralize Initiative routing, manageability, loading, and board status helpers
• expand cross-repository contract checks to modular API clients and board statuses
• replace the oversized Initiative header container with the shared page-header and metric grammar

Why

The inline creation form crowded the board, empty workspaces hid the board structure, and cards had no supported deletion path. The audit also found repeated routing and permission rules plus a contract test that ignored modular Initiative API files.

Validation

• yarn typecheck
• yarn test (139 tests)
• yarn build
• populated local preview with create/move/delete verification

Temporary preview data lives outside the repository.