Initial commit: boarding pass to AirTrail pipeline

Photograph/screenshot a boarding pass, decode its BCBP barcode (PDF417/
Aztec/QR/DataMatrix), fetch the historical flight track from FlightAware
the day after the flight, stage it for review, and write it into AirTrail
via its REST API on approval. ntfy notifications carry signed
Approve/Deny/Investigate actions.

app.py

@@ -0,0 +1,43 @@
+import logging
+import os
+
+from flask import Flask, redirect, send_from_directory, url_for
+from waitress import serve
+
+import config
+import db
+import routes_review
+import routes_settings
+import routes_upload
+import scheduler
+
+logging.basicConfig(level=logging.INFO)
+
+
+def create_app() -> Flask:
+    config.ensure_dirs()
+    db.init_db()
+
+    app = Flask(__name__)
+    app.config["MAX_CONTENT_LENGTH"] = config.MAX_UPLOAD_MB * 1024 * 1024
+
+    app.register_blueprint(routes_upload.bp)
+    app.register_blueprint(routes_review.bp)
+    app.register_blueprint(routes_settings.bp)
+
+    @app.route("/")
+    def index():
+        return redirect(url_for("upload.upload"))
+
+    @app.route("/uploads/<path:name>")
+    def uploaded_file(name):
+        return send_from_directory(config.UPLOADS_DIR, name)
+
+    return app
+
+
+app = create_app()
+
+if __name__ == "__main__":
+    scheduler.start_background_thread()
+    serve(app, host="0.0.0.0", port=config.PORT)