feat(frontend): expose processing tier pricing

frontend/src/features/usage/utils/__tests__/service-tier.spec.ts

@@ -0,0 +1,41 @@
+import { describe, expect, it } from 'vitest'
+
+import {
+  hasServiceTierFact,
+  normalizeServiceTierFact,
+  resolveServiceTierFacts,
+} from '../service-tier'
+
+describe('service tier facts', () => {
+  it('keeps requested, actual and billing tiers independent', () => {
+    const facts = resolveServiceTierFacts({
+      service_tier: 'priority',
+      actual_service_tier: 'default',
+      settlement: {
+        settlement_snapshot: {
+          pricing_snapshot: {
+            requested_processing_tier: 'ignored-requested-snapshot',
+            actual_processing_tier: 'ignored-actual-snapshot',
+            billing_processing_tier: 'standard',
+          },
+        },
+      },
+    })
+
+    expect(facts).toEqual({ requested: 'priority', actual: 'default', billing: 'standard' })
+    expect(hasServiceTierFact(facts)).toBe(true)
+  })
+
+  it('does not infer billing from requested or actual tiers', () => {
+    expect(resolveServiceTierFacts({
+      service_tier: 'priority',
+      actual_service_tier: 'flex',
+    })).toEqual({ requested: 'priority', actual: 'flex', billing: null })
+  })
+
+  it('normalizes only non-empty string facts', () => {
+    expect(normalizeServiceTierFact('  Batch  ')).toBe('Batch')
+    expect(normalizeServiceTierFact('  ')).toBeNull()
+    expect(normalizeServiceTierFact(0)).toBeNull()
+  })
+})

frontend/src/features/usage/utils/service-tier.ts

@@ -0,0 +1,40 @@
+export interface ServiceTierFacts {
+  requested: string | null
+  actual: string | null
+  billing: string | null
+}
+
+export interface ServiceTierFactSource {
+  service_tier?: unknown
+  actual_service_tier?: unknown
+  settlement?: unknown
+}
+
+export function resolveServiceTierFacts(
+  source: ServiceTierFactSource | null | undefined,
+): ServiceTierFacts {
+  const settlement = asRecord(source?.settlement)
+  const settlementSnapshot = asRecord(settlement?.settlement_snapshot)
+  const pricingSnapshot = asRecord(settlementSnapshot?.pricing_snapshot)
+  return {
+    requested: normalizeServiceTierFact(source?.service_tier),
+    actual: normalizeServiceTierFact(source?.actual_service_tier),
+    billing: normalizeServiceTierFact(pricingSnapshot?.billing_processing_tier),
+  }
+}
+
+export function hasServiceTierFact(facts: ServiceTierFacts): boolean {
+  return facts.requested !== null || facts.actual !== null || facts.billing !== null
+}
+
+export function normalizeServiceTierFact(value: unknown): string | null {
+  if (typeof value !== 'string') return null
+  const normalized = value.trim()
+  return normalized || null
+}
+
+function asRecord(value: unknown): Record<string, unknown> | null {
+  return value !== null && typeof value === 'object' && !Array.isArray(value)
+    ? value as Record<string, unknown>
+    : null
+}