ems-core v1.0.0: Standard EMS platform core

Shared backend + frontend for multi-customer EMS deployments.
- 12 enterprise modules: quota, cost, charging, maintenance, analysis, etc.
- 120+ API endpoints, 37 database tables
- Customer config mechanism (CUSTOMER env var + YAML config)
- Collectors: Modbus TCP, MQTT, HTTP API, Sungrow iSolarCloud
- Frontend: React 19 + Ant Design + ECharts + Three.js
- Infrastructure: Redis cache, rate limiting, aggregation engine

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/alembic/env.py

@@ -0,0 +1,49 @@
+from logging.config import fileConfig
+from sqlalchemy import engine_from_config, pool
+from alembic import context
+import sys
+import os
+
+sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
+from app.core.config import get_settings
+from app.core.database import Base
+from app.models import *  # noqa
+
+config = context.config
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# Override sqlalchemy.url from app settings (supports .env override)
+app_settings = get_settings()
+config.set_main_option("sqlalchemy.url", app_settings.DATABASE_URL_SYNC)
+
+target_metadata = Base.metadata
+
+
+def run_migrations_offline():
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(url=url, target_metadata=target_metadata, literal_binds=True)
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online():
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata,
+            render_as_batch=True,
+        )
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()