web: settings profile - preferred currency and default alert days

[rghvgrv]

Parent

#196 — PRD: Angular web client for SubVora (parity minus reminders)

What to build

The settings screen's profile card: the signed-in email (read-only), the preferred (home) currency, and the default alert days that per-subscription alerts inherit. Changing the currency must invalidate the dashboard so totals refetch converted into the new home currency rather than sitting there wrong.

Implementation Steps

1. API service — core/api/users-api.service.ts with getMe() and updateMe({ preferredCurrency, defaultAlertDaysAdvance }), both typed to UserProfile.
2. Store — features/settings/settings.store.ts: profile signal, load(), saveProfile(); failures via the write-failure mapper.
3. Screen — features/settings/settings.component.ts with a profile card: email shown but disabled, currency select over the ISO-4217 list from slice 6, default alert days (blank allowed, otherwise 1–365). Lazily-loaded /settings route behind authGuard, linked from the shell nav.
4. Invalidate dependents — after a successful currency change, clear the dashboard store's cached burn rate so the next visit refetches; if the dashboard is the active screen, reload it immediately.
5. Spec — settings.store.spec.ts: a save sends both fields and updates the profile signal; blank alert days is sent as null, not 0; a currency change invalidates the dashboard; a 400 maps onto the right control.

Agent Routing

agent_routing:
  complexity_hint: easy
  required_capability: balanced
  parallel_safe: true
  cost_preference: low
  speed_preference: balanced
  ownership_scope:
    - src/SubVora.Web/src/app/core/api/users-api.service.ts
    - src/SubVora.Web/src/app/features/settings/**
    - src/SubVora.Web/src/app/app.routes.ts
  verification:
    - cd src/SubVora.Web && npx ng test --no-watch

Technical Context Snapshot

Current stack in scope

• UI: Angular (20+) standalone components with signals and built-in control flow, Angular Material (Material 3) as the only component library, SCSS. Static SPA — no SSR, no service worker.
• State: signal-backed injectable stores, one per domain area, mirroring the MAUI ViewModel split in src/SubVora.Mobile/ViewModels one-to-one. No NgRx.
• API access: hand-written models plus one service per API controller under src/SubVora.Web/src/app/core/api. Enums travel as JSON strings (JsonStringEnumConverter in Program.cs), so TypeScript string-literal unions are exact.
• Backend consumed unchanged: ASP.NET Core net10.0, /api/v1/, JWT bearer in the Authorization header, tokens in JSON bodies (no cookies).
• Tests: Angular CLI unit-test builder (Vitest runner; Karma is deprecated) with HttpTestingController. Stores, interceptors, mappers and utils only — no component-DOM or browser automation.

Dependencies in scope

• Reuse: @angular/*, @angular/material, rxjs, and the utilities already added under src/SubVora.Web/src/app/core. No chart library, no date library, no HTTP wrapper library.
• New dependency additions allowed for this slice: no. If a dependency looks unavoidable, stop and raise it on the issue rather than adding it.

Architecture alignment

• Preserve the repo's load-bearing rules (CLAUDE.md): burn-rate maths is server-side and counts cycles, never days; currency conversion is a read-time projection and stored amounts are never overwritten; nothing advances next_billing_date on a timer; provider matching stays one SQL query; the mobile SQLite cache stays a read-only mirror.
• There is deliberately no shared DTO project. Web models mirror the API's JSON contract by convention — a contract change means editing both sides.
• create-git-issue provides routing hints only and assigns no concrete agent or model.
• run-with-it remains the final runtime routing authority.

Integration touchpoints

• Consumes GET and PUT /api/v1/users/me returning { id, email, preferredCurrency, defaultAlertDaysAdvance }.
• Mirrors UpdateUserProfileRequestValidator: currency required, 3 characters, valid ISO-4217; default alert days null or 1-365.
• The preferred currency is the home currency the server converts dashboard totals into, so changing it changes every total.
• This default does not change any subscription's own alert_days_advance override.

Acceptance criteria

• The profile loads and both fields save, with a blank alert-days field sent as null.
• Changing the preferred currency causes dashboard totals to be refetched in the new currency.
• Email is displayed but not editable, and validation mirrors the server's rules.

Blocked by

• web: auth interceptor with proactive and single-flight token refresh #205 (slice 9)