Add ledger account descriptions

[nirzaf]

Fixes #4

Add basic descriptions for each account in the default chart of accounts and move the "Chart of Accounts" section to the "Basics" section in the sidebar.

• docs/miscellaneous/chart-of-accounts.md

  • Add basic descriptions for each account in the default chart of accounts under a new section "Default Chart of Accounts".
  • Include descriptions for accounts under Assets, Liabilities, Equity, Income, and Expenses categories.

• docs/.vitepress/sidebar.ts

  • Move the "Chart of Accounts" section to the "Basics" section in the sidebar.