refactor(admin-panel): move entity tightly coupled to entities into app

[sandipndev]

more readable app directory. this pr brings in all components that interact with the GQL api into app for better cohesion and easier navigation.

├── customers
│   ├── create.tsx
│   ├── [customer-id]
│   │   ├── deposits.tsx
│   │   ├── details.tsx
│   │   ├── loans.tsx
│   │   ├── page.tsx
│   │   └── withdrawals.tsx
│   ├── list.tsx
│   ├── page.tsx
│   └── server-actions.ts
├── deposits
│   ├── page.tsx
│   └── record.tsx
├── loans
│   ├── approve.tsx
│   ├── create.tsx
│   ├── [loan-id]
│   │   ├── details.tsx
│   │   └── page.tsx
│   ├── loans-table.tsx
│   ├── page.tsx
│   ├── partial-payment.tsx
│   ├── status-badge.tsx
│   ├── update-collateralization-state.tsx
│   └── update-collateral.tsx

future objective for this refactor is to use the items is a modular fashion. for eg, the list on loans can be used on customer detail to show loans for only specific user.