Peer enhancements: notes, traffic quotas with auto-disable, batch create, usage tracking; relay subnets for bridging into other tunnels

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

app/db.py

@@ -1,4 +1,4 @@
-from sqlalchemy import create_engine
+from sqlalchemy import create_engine, text
 from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
 
 from .config import settings
@@ -21,3 +21,24 @@ def get_db():
         yield db
     finally:
         db.close()
+
+
+PEER_MIGRATIONS = {
+    "note": "ALTER TABLE peers ADD COLUMN note VARCHAR(256) NOT NULL DEFAULT ''",
+    "quota_bytes": "ALTER TABLE peers ADD COLUMN quota_bytes INTEGER NOT NULL DEFAULT 0",
+    "cum_rx": "ALTER TABLE peers ADD COLUMN cum_rx INTEGER NOT NULL DEFAULT 0",
+    "cum_tx": "ALTER TABLE peers ADD COLUMN cum_tx INTEGER NOT NULL DEFAULT 0",
+    "last_rx": "ALTER TABLE peers ADD COLUMN last_rx INTEGER NOT NULL DEFAULT 0",
+    "last_tx": "ALTER TABLE peers ADD COLUMN last_tx INTEGER NOT NULL DEFAULT 0",
+}
+
+
+def run_migrations() -> None:
+    with engine.connect() as conn:
+        existing = {
+            row[1] for row in conn.execute(text("PRAGMA table_info(peers)"))
+        }
+        for column, ddl in PEER_MIGRATIONS.items():
+            if existing and column not in existing:
+                conn.execute(text(ddl))
+        conn.commit()