Add pensions module and integrate with tax report

Adds a full pensions feature: SIPP/workplace DC/LISA account metadata,
contribution recording with relief-at-source/net-pay/salary-sacrifice
gross calculations, state pension tracker, annual allowance monitor,
and LISA summary. Pension contributions feed into the tax report
(RAS gross totals, allowance used). Includes two Alembic migrations,
backend service/schema/API, and full frontend pensions page with
cards for allowance, state pension, LISA, and retirement projection.

Also fixes CSRF cookie secure flag (must be false for HTTP deployments)
and extends tax schemas/service to expose pension data in the report.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/schemas/pension.py

@@ -0,0 +1,195 @@
+import uuid
+from datetime import date as DateType, datetime
+from decimal import Decimal
+from typing import Literal
+
+from pydantic import BaseModel, Field, model_validator
+
+PensionType = Literal["workplace_dc", "workplace_db", "sipp", "lisa"]
+ReliefType = Literal["relief_at_source", "net_pay", "salary_sacrifice", "none"]
+
+
+class PensionMetadataCreate(BaseModel):
+    pension_type: PensionType
+    provider_name: str | None = None
+    scheme_name: str | None = None
+    member_reference: str | None = None
+    dob: DateType | None = None
+    target_retirement_age: int | None = Field(default=None, ge=55, le=90)
+    assumed_growth_rate: Decimal | None = Field(default=None, ge=0, le=1)
+
+
+class PensionMetadataUpdate(BaseModel):
+    pension_type: PensionType | None = None
+    provider_name: str | None = None
+    scheme_name: str | None = None
+    member_reference: str | None = None
+    dob: DateType | None = None
+    target_retirement_age: int | None = Field(default=None, ge=55, le=90)
+    assumed_growth_rate: Decimal | None = Field(default=None, ge=0, le=1)
+
+
+class PensionMetadataResponse(BaseModel):
+    id: uuid.UUID
+    account_id: uuid.UUID
+    pension_type: PensionType
+    provider_name: str | None
+    scheme_name: str | None
+    member_reference: str | None
+    dob: DateType | None
+    target_retirement_age: int | None
+    assumed_growth_rate: Decimal | None
+    created_at: datetime
+    updated_at: datetime
+
+    model_config = {"from_attributes": True}
+
+
+class PensionContributionCreate(BaseModel):
+    contribution_date: DateType
+    member_amount: Decimal = Field(..., ge=0)
+    employer_amount: Decimal = Field(default=Decimal("0"), ge=0)
+    relief_type: ReliefType
+    notes: str | None = None
+
+    @model_validator(mode="after")
+    def check_amounts(self) -> "PensionContributionCreate":
+        if self.member_amount == 0 and self.employer_amount == 0:
+            raise ValueError("At least one of member_amount or employer_amount must be greater than 0")
+        return self
+
+
+class PensionContributionUpdate(BaseModel):
+    contribution_date: DateType | None = None
+    member_amount: Decimal | None = Field(default=None, ge=0)
+    employer_amount: Decimal | None = Field(default=None, ge=0)
+    relief_type: ReliefType | None = None
+    notes: str | None = None
+
+
+class PensionContributionResponse(BaseModel):
+    id: uuid.UUID
+    pension_id: uuid.UUID
+    contribution_date: DateType
+    tax_year: int
+    member_amount: Decimal
+    employer_amount: Decimal
+    relief_type: ReliefType
+    gross_amount: Decimal
+    relief_amount: Decimal
+    notes: str | None
+    created_at: datetime
+
+    model_config = {"from_attributes": True}
+
+
+class YtdSummary(BaseModel):
+    tax_year: int
+    member_total: Decimal
+    employer_total: Decimal
+    gross_total: Decimal
+    relief_total: Decimal
+    contribution_count: int
+
+
+class PensionAccountResponse(BaseModel):
+    """Account row joined with pension metadata and YTD summary."""
+    account_id: uuid.UUID
+    account_name: str
+    current_balance: Decimal
+    currency: str
+    color: str
+    metadata: PensionMetadataResponse | None
+    ytd: YtdSummary | None
+
+
+_FULL_SP_WEEKLY = Decimal("221.80")
+_SP_AGE = 67
+
+
+class StatePensionCreate(BaseModel):
+    qualifying_years: int = Field(..., ge=0, le=50)
+    checked_date: DateType | None = None
+
+
+class StatePensionResponse(BaseModel):
+    id: uuid.UUID
+    qualifying_years: int
+    checked_date: DateType | None
+    weekly_amount: Decimal
+    annual_amount: Decimal
+    is_full_pension: bool
+    years_to_full: int
+    state_pension_age: int
+
+    model_config = {"from_attributes": True}
+
+
+class ProjectionScenario(BaseModel):
+    label: str
+    growth_rate: Decimal
+    projected_pot: Decimal
+    annual_drawdown_4pct: Decimal
+    annual_drawdown_3pct: Decimal
+
+
+class ChartDataPoint(BaseModel):
+    year: int
+    pot_2pct: Decimal
+    pot_5pct: Decimal
+    pot_8pct: Decimal
+
+
+class RetirementProjection(BaseModel):
+    account_id: uuid.UUID
+    account_name: str
+    current_balance: Decimal
+    years_to_retirement: int
+    target_retirement_age: int
+    scenarios: list[ProjectionScenario]
+    state_pension_annual: Decimal | None
+    state_pension_age: int
+    chart_data: list[ChartDataPoint]
+
+
+class LisaTaxYearBreakdown(BaseModel):
+    tax_year: int
+    contributions: Decimal
+    bonus_expected: Decimal
+    limit_remaining: Decimal
+    limit_used_pct: Decimal
+
+
+class LisaSummary(BaseModel):
+    account_id: uuid.UUID
+    account_name: str
+    tax_year_breakdown: list[LisaTaxYearBreakdown]
+    current_year_contributions: Decimal
+    current_year_bonus_expected: Decimal
+    current_year_limit_remaining: Decimal
+    total_contributions: Decimal
+    total_bonus_expected: Decimal
+    account_opened_date: datetime
+    withdrawal_penalty_amount: Decimal
+    withdrawal_penalty_pct: Decimal
+    penalty_warning: bool
+
+
+class CarryForwardYear(BaseModel):
+    tax_year: int
+    standard_allowance: Decimal
+    contributions: Decimal
+    unused: Decimal
+
+
+class AllowanceSummary(BaseModel):
+    tax_year: int
+    standard_allowance: Decimal
+    contributions_total: Decimal
+    remaining: Decimal
+    carry_forward: list[CarryForwardYear]
+    carry_forward_total: Decimal
+    total_available: Decimal
+    relief_ras_total: Decimal
+    relief_higher_rate_claimable: Decimal
+    relief_additional_rate_claimable: Decimal