Refactor event and session column names to camelCase

- Updated test cases to reflect new column names (eve_MAC -> eveMac, eve_DateTime -> eveDateTime, etc.) across various test files.
- Modified SQL table definitions in the database cleanup and migration tests to use camelCase naming conventions.
- Implemented migration tests to ensure legacy column names are correctly renamed to camelCase equivalents.
- Ensured that existing data is preserved during the migration process and that views referencing old column names are dropped before renaming.
- Verified that the migration function is idempotent, allowing for safe re-execution without data loss.

server/database.py

@@ -16,6 +16,7 @@ from db.db_upgrade import (
     ensure_Settings,
     ensure_Indexes,
     ensure_mac_lowercase_triggers,
+    migrate_to_camelcase,
     migrate_timestamps_to_utc,
 )
 
@@ -194,6 +195,10 @@ class DB:
             if not ensure_column(self.sql, "Devices", "devCanSleep", "INTEGER"):
                 raise RuntimeError("ensure_column(devCanSleep) failed")
 
+            # CamelCase column migration (must run before UTC migration and
+            # before ensure_plugins_tables which uses IF NOT EXISTS with new names)
+            migrate_to_camelcase(self.sql)
+
             # Settings table setup
             ensure_Settings(self.sql)