Add endpoint tests and consolidate test directory

- Add HTTP endpoint tests to mimic browser interactions
- Move old test files from test/ to tests/ directory
- Add comprehensive endpoint tests for tabs, profiles, presets, patterns
- Add README documenting test structure and how to run tests

tests/test_main_old.py

@@ -0,0 +1,12 @@
+from microdot import Microdot
+from src.profile import profile_app
+
+app = Microdot()
+
+@app.route('/')
+async def index(request):
+    return 'Hello, world!'
+
+app.mount(profile_app, url_prefix="/profile")
+
+app.run(port=8080, debug=True)