Add M365 mapping/prices export-import, license pricing, and PDF summary export

- Mapping (Username/QWE Client/IsRestaurant): CSV export and import via new routes
- License prices: persistent DB table (M365LicensePrice), editable price card with auto-save, CSV export/import
- Summary table: Monthly Cost column per client + grand-total row, calculated live in JS from current prices
- PDF export: client-side jsPDF/autotable, landscape A4, includes cost column when prices are set

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

app/database.py

@@ -1,6 +1,6 @@
 import os
 import datetime
-from sqlalchemy import create_engine, Column, Integer, String, DateTime, Boolean
+from sqlalchemy import create_engine, Column, Integer, String, DateTime, Boolean, Float
 from sqlalchemy.orm import declarative_base, sessionmaker
 
 DATABASE_URL = f"sqlite:///{os.getenv('DB_PATH', '/data/audit.db')}"
@@ -19,6 +19,14 @@ class M365UserOverride(Base):
     updated_at = Column(DateTime, default=datetime.datetime.utcnow)
 
 
+class M365LicensePrice(Base):
+    __tablename__ = "m365_license_prices"
+
+    license_key = Column(String, primary_key=True)
+    price = Column(Float, default=0.0, nullable=False)
+    updated_at = Column(DateTime, default=datetime.datetime.utcnow)
+
+
 class RebootLog(Base):
     __tablename__ = "reboot_log"