Full test infrastructure, code audit fixes, and real E2E integration tests

Test infrastructure:
- Django standalone test runner (pytest-django, test settings, EmailUser model)
- React unit tests via Vitest with jsdom, jest compat layer, path aliases
- Playwright E2E tests using generated hooks in a real Chromium browser
- Docker Compose test backend (Django + Redis) for integration testing
- Desktop integration test app (PyWebView + Django + uvicorn)
- Makefile with test/test-django/test-react/test-integration targets

Library bugs found and fixed:
- hasJWT truthiness: undefined !== null was true, skipping session init
- process.env crash: CSR client referenced process.env in non-Node browsers
- baseUrl not forwarded: DjareaProvider didn't pass baseUrl to CSR client
- Relative URL handling: new URL() failed with relative base paths
- call() race condition: HTTP requests fired before CSRF cookie was set
- Session init await: added sessionRef promise so call() waits for session
- path_prefix on schema export: both export commands failed with URL reverse
- NullBooleanField removed: referenced field doesn't exist in Django 5.0+
- lru_cache on JWT settings: get_settings() now cached as intended
- Channel message routing: broadcasts now include channel name and params
- httpFunctionCall: fixed URL and request body format

Generator fixes:
- Removed 1,100 lines of REST/OpenAPI client generation (not part of Djarea)
- Generator now works for djarea-only projects without django-ninja REST APIs
- Generated DjangoContext now includes ChannelProvider when channels exist
- Fixed env var passthrough for schema export commands
- Deduplicated fetch logic into single runDjangoCommand helper

Test quality:
- Fixed 33 tautological Django tests with real assertions
- Found hidden bug: benchmark functions were never registered
- Found hidden bug: unicode lookalike test used plain ASCII
- Deleted worthless React unit tests (duplicates, shape checks, Zod-tests-Zod)
- Replaced jsdom integration tests with Playwright browser tests

Example apps:
- example/: Integration test backend with 33 server functions, 5 forms,
  4 channels covering auth variations, contexts, class-based ServerFunction,
  error codes, DjareaFormMixin, formsets, and JWT
- desktop/: PyWebView desktop app with file system access, SQLite CRUD,
  system introspection, and 39 real HTTP integration tests

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Dockerfile.test

@@ -0,0 +1,21 @@
+FROM python:3.12-slim
+
+WORKDIR /app
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    gcc \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install djarea from local source with channels support
+COPY django/ /app/django/
+RUN pip install --no-cache-dir /app/django[channels] daphne
+
+# Copy example app
+COPY example/ /app/example/
+
+WORKDIR /app/example
+
+EXPOSE 8000
+
+CMD ["sh", "-c", "python manage.py migrate --run-syncdb && daphne -b 0.0.0.0 -p 8000 testapp.asgi:application"]