feat: full integration — app.py wiring, scheduler startup, route registration, README

- Wire blueprints and scheduler into create_app()
- Add start_scheduler param to skip scheduler in tests
- Fix Setting.get/set to use modern db.session.get()
- Remove unused imports from conftest and models
- Add README with quick start and usage guide

Made-with: Cursor

tests/conftest.py

@@ -1,5 +1,3 @@
-import os
-import tempfile
 import pytest
 from app import create_app, db as _db
 import config
@@ -12,7 +10,7 @@ def app(tmp_path):
     config.ISSUES_DIR = str(tmp_path / "data" / "issues")
     config.SQLALCHEMY_DATABASE_URI = f"sqlite:///{tmp_path / 'test.db'}"
 
-    app = create_app()
+    app = create_app(start_scheduler=False)
     app.config["TESTING"] = True
 
     with app.app_context():