fix: add unified ledger amount and enforce manual decimal precision

Co-authored-by: genichin <4282227+genichin@users.noreply.github.com>

app/api/v1_portfolios.py

@@ -769,16 +769,18 @@ def _decode_ledger_cursor(cursor: str, *, portfolio_id: str, source: str | None)
 
 
 def _ledger_entry_to_history_item(entry) -> LedgerHistoryItem:
+    action = (entry.action or entry.side or "").upper()
     return LedgerHistoryItem(
         ledger_entry_id=entry.ledger_entry_id,
         portfolio_id=entry.portfolio_id,
         source=entry.source or "broker",
-        action=(entry.action or entry.side or "").upper(),
+        action=action,
         recorded_at=entry.recorded_at,
         executed_at=entry.executed_at,
         order_id=entry.order_id,
         execution_id=entry.execution_id,
         quantity=entry.quantity,
+        amount=entry.price if action in {"INVEST", "BUFFER_OUT", "BUFFER_IN", "WITHDRAW", "PROFIT", "DIVIDEND"} else None,
         price=entry.price,
         fee_amount=entry.fee_amount,
         tax_amount=entry.tax_amount,
@@ -825,11 +827,11 @@ def record_manual_ledger_v1(
         entry = repo.record_manual_ledger(
             portfolio_id,
             action=body.action,
-            amount=float(body.amount) if body.amount is not None else None,
-            quantity=float(body.quantity) if body.quantity is not None else None,
-            price=float(body.price) if body.price is not None else None,
-            fee=float(body.fee),
-            tax=float(body.tax),
+            amount=body.amount,
+            quantity=body.quantity,
+            price=body.price,
+            fee=body.fee,
+            tax=body.tax,
             executed_at=(
                 datetime(
                     body.executed_at.year,