This commit extends the "Untrack Account" feature by applying a special style to transaction items that belong to an untracked account.
- The transaction item template is modified to apply a "dimmed" style to transactions from untracked accounts.
- The styling follows the precedence: Account (untracked) > Category (muted) > Transaction (hidden).
- The dropdown menu for transaction items now shows "Controlled by account" if the transaction's account is untracked.