Remove Ahorro from budget UI, add SALARY type and savings auto-accrual

Ahorro was already deducted from gross salary so displaying it in
budget projections was misleading. This removes the Ahorro card,
summary line, Proyecciones column, and Ahorro Anual card from the UI,
and strips all savings fields from budget API responses.

Adds SALARY TransactionType so salary deposits can be distinguished
from generic DEPOSITO transfers. When a SALARY transaction arrives,
the system auto-increments MEMP and MPAT savings account balances
(+200K CRC each) once per month via an idempotent accrual log.

New CRUD endpoints at /api/v1/savings-accrual/ allow manual correction
of the accrual history. Feb+Mar 2026 are seeded as historical baseline.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/app/api/v1/endpoints/budget.py

@@ -39,7 +39,9 @@ def list_recurring_items(
     session: Session = Depends(get_session),
     _user: str = Depends(get_current_user),
 ):
-    query = select(RecurringItem)
+    query = select(RecurringItem).where(
+        RecurringItem.item_type != RecurringItemType.SAVINGS
+    )
     if item_type:
         query = query.where(RecurringItem.item_type == item_type)
     if is_active is not None:
@@ -101,7 +103,6 @@ class MonthlyProjectionResponse(BaseModel):
     year: int
     projected_income: float
     projected_fixed_expenses: float
-    projected_savings: float
     actual_credit_card: float
     actual_cash: float
     actual_transfers: float
@@ -118,7 +119,6 @@ class YearlyProjectionResponse(BaseModel):
     months: list[MonthlyProjectionResponse]
     annual_income: float
     annual_expenses: float
-    annual_savings: float
     annual_net: float
 
 
@@ -138,7 +138,6 @@ def get_yearly_projection(
     months = []
     annual_income = 0.0
     annual_expenses = 0.0
-    annual_savings = 0.0
     annual_net = 0.0
 
     for data in months_data:
@@ -147,7 +146,6 @@ def get_yearly_projection(
             year=data["year"],
             projected_income=data["projected_income"],
             projected_fixed_expenses=data["projected_fixed_expenses"],
-            projected_savings=data["projected_savings"],
             actual_credit_card=data["actual_credit_card"],
             actual_cash=data["actual_cash"],
             actual_transfers=data["actual_transfers"],
@@ -161,7 +159,6 @@ def get_yearly_projection(
         months.append(monthly)
         annual_income += data["projected_income"]
         annual_expenses += data["gran_total_egresos"]
-        annual_savings += data["projected_savings"]
         annual_net += data["net_balance"]
 
     return YearlyProjectionResponse(
@@ -169,7 +166,6 @@ def get_yearly_projection(
         months=months,
         annual_income=annual_income,
         annual_expenses=annual_expenses,
-        annual_savings=annual_savings,
         annual_net=annual_net,
     )
 
@@ -204,11 +200,9 @@ class MonthlyDetailResponse(BaseModel):
     month: int
     income_items: list[RecurringItemDetail]
     expense_items: list[RecurringItemDetail]
-    savings_items: list[RecurringItemDetail]
     actuals_by_source: list[ActualsBySource]
     total_projected_income: float
     total_projected_expenses: float
-    total_projected_savings: float
     uncovered_actual: float
     gran_total_egresos: float
     net_balance: float
@@ -228,11 +222,9 @@ def get_monthly_detail(
         month=data["month"],
         income_items=[RecurringItemDetail(**i) for i in data["income_items"]],
         expense_items=[RecurringItemDetail(**i) for i in data["expense_items"]],
-        savings_items=[RecurringItemDetail(**i) for i in data["savings_items"]],
         actuals_by_source=[ActualsBySource(**a) for a in data["actuals_by_source"]],
         total_projected_income=data["projected_income"],
         total_projected_expenses=data["projected_fixed_expenses"],
-        total_projected_savings=data["projected_savings"],
         uncovered_actual=data["uncovered_actual"],
         gran_total_egresos=data["gran_total_egresos"],
         net_balance=data["net_balance"],