test: add EDR passenger pricing/config E2E bug-hunt harness

Hermetic E2E harness targeting pricing integrity and backoffice config:
- e2e/ docker Postgres (5544) + prepare.sh/run.sh one-command runner + HTML report
- 6 suites / 23 tests reproducing pricing, FX, wallet, refund, config and auth
  defects (see docs/ISSUES.md); docs/e2e-test-matrix.md documents the matrix
- two-tier harness (slim module boot + direct service instantiation) to work
  around the IAM/RabbitMQ/file-type boot wall
- .env.test.example tracked; loader falls back to it for fresh checkouts

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

e2e/README.md

@@ -0,0 +1,76 @@
+# EDR Passenger — Pricing/Config E2E Harness
+
+Hermetic, bug-hunting test harness for the passenger platform. Targets **pricing integrity** and
+**backoffice configuration**. Never touches a real database.
+
+## Quick start
+
+```bash
+# 1. Bring up the isolated test Postgres (port 5544) and apply all migrations
+bash e2e/prepare.sh
+#    (or: pnpm --filter @edr/passenger-api test:e2e:prepare)
+
+# 2. Run the suites
+pnpm --filter @edr/passenger-api test:e2e
+
+# 3. Tear down
+pnpm --filter @edr/passenger-api test:e2e:db:down
+```
+
+## What's isolated
+
+- `e2e/docker-compose.yml` — Postgres 17 on host port **5544**, container `edr-passenger-e2e-db`,
+  `tmpfs` data (wiped on `down`). Distinct from any dev/prod DB. Schemas `passenger`, `iam`,
+  `edr_payment` created by `e2e/init/01-schemas.sql`.
+- `apps/edr-passenger-api/.env.test` — points every connection at 5544; brokers/IAM/Fayda OFF.
+  Loaded by `test/setup/load-env.ts` before the app boots.
+
+## Architecture — why two tiers
+
+The full `AppModule` cannot be booted in-process under jest:
+- `@tria-plc/api-common` (pulled via IAM) `require("file-type")`, which is ESM-only → jest's
+  CommonJS resolver fails. (Worked around with a `moduleNameMapper` stub, but…)
+- `@golevelup/nestjs-rabbitmq` + microservice RMQ clients + `onApplicationBootstrap` seeders hang
+  the boot waiting on a broker that isn't there.
+
+So tests use one of two tiers:
+
+**Tier 1 — slim module harness** (`test/setup/slim-app.ts`). Boots ONLY the pricing/config domain
+modules that are free of the IAM/RabbitMQ chain: `fare-engine, currency, currencies, promos,
+seat-classes, stations, schedules, segments, system-config`. Two entry points:
+- `createServiceHarness()` — resolve services (e.g. `FareEngineService`) for direct method calls.
+- `createHttpHarness()` — full HTTP app with the SAME `ValidationPipe` as `src/main.ts`, for
+  controller/DTO/pipe (client-trust, validation) tests over supertest.
+
+**Tier 2 — direct instantiation** (`test/setup/prisma.ts`). For services behind the wall
+(`BookingsService, PaymentsService, WalletService, LoyaltyService, ExcessBaggageService`):
+`new TheService(getTestPrisma(), ...mockedCollaborators)` and assert the money logic. Avoids booting
+the module graph entirely.
+
+## Fixtures
+
+`test/fixtures/seed-core.ts` — deterministic graph (coach type → LOCAL/INTERNATIONAL seat classes →
+3 stations → route with distance-bearing stops → FX rates) with fixed UUIDs in `IDS`. Call
+`resetAndSeedCore(prisma)` in `beforeEach`. The repo's `prisma/seed.ts` is disabled (all steps
+commented out) and is intentionally NOT used.
+
+## Suites (see `docs/e2e-test-matrix.md` for the full matrix)
+
+Spec files are `test/*.e2e-spec.ts`. Each is tagged with the matrix IDs it covers. 🔴 in a test name
+marks a confirmed defect the test documents/reproduces (the assertion encodes the BUGGY behavior;
+a passing 🔴 test = the bug is present).
+
+Current suites (all green):
+- `pricing-fare-engine.e2e-spec.ts` — baseline + D1/D2/D4 (promo → negative total), C1 (FX fallback)
+- `pricing-currency.e2e-spec.ts` — C2/C2b (display↔charge FX divergence), C3 (future rate), C5 (unit divergence)
+- `money-integrity.e2e-spec.ts` — F1/F2 (free wallet top-up), G4/G5 (refund never disbursed), E1/E2 (baggage)
+- `config-validation.e2e-spec.ts` — H1/H2 (negative fares), H4/H5 (promo bounds/date)
+- `auth-gaps.e2e-spec.ts` — J1 (unauthenticated FX writes)
+- `critical-repro.e2e-spec.ts` — C-1 (client-controlled booking total), C-4 (payment amount never
+  validated), C-6 (wallet double-spend via a deterministic race barrier)
+
+`test/app.e2e-spec.ts` is a pre-existing repo test that boots the FULL AppModule; it is excluded via
+`testPathIgnorePatterns` because that boot hangs in-process (RabbitMQ connect + ESM `file-type`) — a
+harness limitation documented above, not a product bug.
+
+Findings are catalogued in `docs/ISSUES.md`.