Account Mapping Configuration UI

Build UI for mapping QuickBooks accounts to Costpoint accounts with project code rules.

Note: - Display table with all QuickBooks accounts (one row per QB account) - Each row shows: QB account name, QB account type, Costpoint account selector, project code rule selector - Costpoint account selector: dropdown/autocomplete with Costpoint accounts loaded from API - Project code rule options: "None" (balance sheet accounts), "Required" (P&L accounts), or specific project code - Smart defaults: balance sheet accounts default to "None", revenue/expense accounts default to "Required" - Visual indicators: highlight unmapped accounts, show validation errors - Filter/search functionality for large account lists - Bulk actions: set multiple accounts to same Costpoint account or project rule - Save/cancel actions with unsaved changes warning - Reference PoC mapping table UI design

Open questions: - Should we support mapping templates or preset configurations?