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/versions/006_pricing_tables.py

@@ -0,0 +1,48 @@
+"""Add pricing tables
+
+Revision ID: 006_pricing
+Revises: 005_quota
+Create Date: 2026-04-03
+"""
+from alembic import op
+import sqlalchemy as sa
+
+revision = "006_pricing"
+down_revision = "005_quota"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    # --- electricity_pricing ---
+    op.create_table(
+        "electricity_pricing",
+        sa.Column("id", sa.Integer, primary_key=True, autoincrement=True),
+        sa.Column("name", sa.String(200), nullable=False),
+        sa.Column("energy_type", sa.String(50), default="electricity"),
+        sa.Column("pricing_type", sa.String(20), nullable=False),
+        sa.Column("effective_from", sa.DateTime(timezone=True)),
+        sa.Column("effective_to", sa.DateTime(timezone=True)),
+        sa.Column("is_active", sa.Boolean, default=True),
+        sa.Column("created_by", sa.Integer, sa.ForeignKey("users.id")),
+        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
+        sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
+    )
+
+    # --- pricing_periods ---
+    op.create_table(
+        "pricing_periods",
+        sa.Column("id", sa.Integer, primary_key=True, autoincrement=True),
+        sa.Column("pricing_id", sa.Integer, sa.ForeignKey("electricity_pricing.id"), nullable=False),
+        sa.Column("period_name", sa.String(50), nullable=False),
+        sa.Column("start_time", sa.String(10), nullable=False),
+        sa.Column("end_time", sa.String(10), nullable=False),
+        sa.Column("price_per_unit", sa.Float, nullable=False),
+        sa.Column("applicable_months", sa.JSON),
+        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
+    )
+
+
+def downgrade() -> None:
+    op.drop_table("pricing_periods")
+    op.drop_table("electricity_pricing")