Rewrite as uv-based Flask web app with Dockerfile

- Flask dashboard with Plotly charts (stores, monthly, hourly, weekday, heatmap)
- Spotify Wrapped-style summary with year dropdown and inflation toggle
- CSV upload flow (ephemeral, no storage)
- Homepage with upload and saved data options
- Import script for loading CSVs into SQLite
- Dockerized with gunicorn for production

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

import_csv.py

@@ -0,0 +1,84 @@
+#!/usr/bin/env python3
+"""Import a DoorDash CSV export into doordash.db."""
+
+import csv
+import sqlite3
+import sys
+from pathlib import Path
+
+DB_PATH = Path(__file__).parent / "doordash.db"
+
+CREATE_TABLE = """CREATE TABLE IF NOT EXISTS "doordash"(
+    "ITEM" TEXT, "CATEGORY" TEXT, "STORE_NAME" TEXT, "UNIT_PRICE" TEXT,
+    "QUANTITY" TEXT, "SUBTOTAL" TEXT, "CREATED_AT" TEXT, "DELIVERY_TIME" TEXT,
+    "DELIVERY_ADDRESS" TEXT
+);"""
+
+EXPECTED_HEADER = [
+    "ITEM", "CATEGORY", "STORE_NAME", "UNIT_PRICE", "QUANTITY",
+    "SUBTOTAL", "CREATED_AT", "DELIVERY_TIME", "DELIVERY_ADDRESS",
+]
+
+
+def import_csv(csv_path: str):
+    path = Path(csv_path)
+    if not path.exists():
+        print(f"Error: {csv_path} not found")
+        sys.exit(1)
+
+    conn = sqlite3.connect(DB_PATH)
+    c = conn.cursor()
+    c.execute(CREATE_TABLE)
+
+    # Get existing row count for reporting
+    before_count = c.execute("SELECT COUNT(*) FROM doordash").fetchone()[0]
+
+    # Check for duplicates using CREATED_AT + ITEM + STORE_NAME
+    existing = set()
+    for row in c.execute("SELECT ITEM, STORE_NAME, CREATED_AT FROM doordash"):
+        existing.add((row[0], row[1], row[2]))
+
+    imported = 0
+    skipped = 0
+
+    with open(path, newline="") as f:
+        reader = csv.reader(f)
+        header = next(reader)
+
+        # Validate header
+        header_upper = [h.strip().upper() for h in header]
+        if header_upper != EXPECTED_HEADER:
+            print(f"Error: unexpected CSV header.\nExpected: {EXPECTED_HEADER}\nGot:      {header_upper}")
+            sys.exit(1)
+
+        for row in reader:
+            if len(row) != 9:
+                print(f"Warning: skipping row with {len(row)} columns: {row[:3]}...")
+                skipped += 1
+                continue
+
+            key = (row[0], row[2], row[6])  # ITEM, STORE_NAME, CREATED_AT
+            if key in existing:
+                skipped += 1
+                continue
+
+            c.execute("INSERT INTO doordash VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)", row)
+            existing.add(key)
+            imported += 1
+
+    conn.commit()
+    after_count = c.execute("SELECT COUNT(*) FROM doordash").fetchone()[0]
+    conn.close()
+
+    print(f"Done! Imported {imported} rows, skipped {skipped} duplicates.")
+    print(f"Total rows: {before_count} -> {after_count}")
+
+
+if __name__ == "__main__":
+    if len(sys.argv) < 2:
+        print(f"Usage: {sys.argv[0]} <csv_file> [csv_file2 ...]")
+        sys.exit(1)
+
+    for csv_file in sys.argv[1:]:
+        print(f"\nImporting {csv_file}...")
+        import_csv(csv_file)