feat!: generic defaults, dashboard fallback, PV filter fix (v1.3.0)

- Replace all hardcoded Tianpu/天普 defaults with generic "EMS Platform"
- Add energy_today fallback: query raw energy_data when daily summary empty
- Fix PV device filter to include sungrow_inverter device type
- Update APP_NAME, CUSTOMER default, SECRET_KEY, SMTP, Celery, email templates

BREAKING: CUSTOMER default changed from "tianpu" to "default"
Existing deployments with CUSTOMER=tianpu in .env are unaffected.

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

backend/app/core/config.py

@@ -6,23 +6,23 @@ import yaml
 
 
 class Settings(BaseSettings):
-    APP_NAME: str = "TianpuEMS"
+    APP_NAME: str = "EMS Platform"
     DEBUG: bool = True
     API_V1_PREFIX: str = "/api/v1"
 
     # Customer configuration
-    CUSTOMER: str = "tianpu"  # tianpu, zpark, etc.
+    CUSTOMER: str = "default"  # tianpu, zpark, etc.
     CUSTOMER_DISPLAY_NAME: str = ""  # Loaded from customer config
 
     # Database: set DATABASE_URL in .env to override.
     # Default: SQLite for local dev. Docker sets PostgreSQL via env var.
     # Examples:
-    #   SQLite:      sqlite+aiosqlite:///./tianpu_ems.db
-    #   PostgreSQL:  postgresql+asyncpg://tianpu:tianpu2026@localhost:5432/tianpu_ems
-    DATABASE_URL: str = "sqlite+aiosqlite:///./tianpu_ems.db"
+    #   SQLite:      sqlite+aiosqlite:///./ems.db
+    #   PostgreSQL:  postgresql+asyncpg://ems:ems2026@localhost:5432/ems
+    DATABASE_URL: str = "sqlite+aiosqlite:///./ems.db"
     REDIS_URL: str = "redis://localhost:6379/0"
 
-    SECRET_KEY: str = "tianpu-ems-secret-key-change-in-production-2026"
+    SECRET_KEY: str = "ems-secret-key-change-in-production-2026"
     ALGORITHM: str = "HS256"
     ACCESS_TOKEN_EXPIRE_MINUTES: int = 480
 
@@ -40,7 +40,7 @@ class Settings(BaseSettings):
     SMTP_PORT: int = 587
     SMTP_USER: str = ""
     SMTP_PASSWORD: str = ""
-    SMTP_FROM: str = "noreply@tianpu-ems.com"
+    SMTP_FROM: str = "noreply@ems-platform.com"
     SMTP_ENABLED: bool = False
 
     # Platform URL for links in emails