Add README and technical docs

- README with quick start, package overview, links to docs
- docs/setup.md — prerequisites, env vars, installation, running, testing
- docs/architecture.md — monorepo structure, backend/frontend design
- docs/api.md — full endpoint reference with permissions
- docs/database.md — schema overview, migrations, multi-tenancy
- docs/testing.md — test runner, suites, writing tests
- Updated .env.example with all supported variables

docs/testing.md

@@ -0,0 +1,81 @@
+# Testing
+
+## API Integration Tests
+
+The primary test suite lives at `packages/backend/api-tests/`. It uses a custom runner that:
+
+1. Creates/migrates a `forte_api_test` database
+2. Seeds company, lookup tables, RBAC permissions/roles
+3. Starts the backend on port 8001
+4. Registers a test user with admin role
+5. Runs test suites via HTTP requests
+6. Tears down the server
+
+### Running
+
+```bash
+cd packages/backend
+source .env    # needs DB credentials
+bun run api-test
+```
+
+### Filtering
+
+```bash
+bun run api-test --suite accounts   # run only the accounts suite
+bun run api-test --tag crud         # run tests tagged 'crud'
+```
+
+### Suites
+
+| Suite | Tests | Coverage |
+|-------|-------|----------|
+| `accounts` | 17 | CRUD, search, pagination, sort, billing mode |
+| `members` | 19 | CRUD, search, move, isMinor, address inheritance |
+| `files` | 7 | Upload, list, get, delete, validation, profile pictures |
+| `rbac` | 21 | Permission enforcement, role CRUD, user status, pagination |
+
+### Writing Tests
+
+Tests are defined in `api-tests/suites/`. Each file exports a suite:
+
+```typescript
+import { suite } from '../lib/context.js'
+
+suite('MyDomain', { tags: ['domain'] }, (t) => {
+  t.test('does something', { tags: ['crud'] }, async () => {
+    const res = await t.api.post('/v1/endpoint', { name: 'Test' })
+    t.assert.status(res, 201)
+    t.assert.equal(res.data.name, 'Test')
+  })
+})
+```
+
+Available on `t`:
+- `t.api` — HTTP client (`get`, `post`, `patch`, `del`) with auth token
+- `t.token` — JWT token string
+- `t.baseUrl` — Backend URL
+- `t.assert` — Assertion helpers (`status`, `equal`, `ok`, `includes`, `greaterThan`, etc.)
+
+### Assert Methods
+
+| Method | Description |
+|--------|-------------|
+| `status(res, code)` | Check HTTP status |
+| `equal(a, b)` | Strict equality |
+| `notEqual(a, b)` | Strict inequality |
+| `ok(value)` | Truthy check |
+| `includes(arr, value)` | Array includes |
+| `contains(str, sub)` | String contains |
+| `greaterThan(a, b)` | Numeric comparison |
+
+## Unit Tests
+
+Unit tests use `bun:test` and live alongside the code or in `__tests__/`:
+
+```bash
+cd packages/backend
+bun run test
+```
+
+Current unit test coverage: shared utils (date helpers, currency formatting, state normalization).