Add system memory monitoring, Bedrock support, and Discord integrations

- Add CPU/GPU memory monitoring endpoint and frontend widget
- Add Amazon Bedrock model support (API key / inference profiles) plus model selector entries
- Add Discord weather/laundry notification job (JMA forecast + LLM-generated message)
- Add Discord bot that replies to mentions via the configured LLM, with weather-aware context
- Add scheduled "useless tips" job with separate webhook and quiet-hours skip
- Switch FastAPI startup to lifespan handler, log viewer, markdown rendering, and toast UI additions

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/db/models.py

@@ -1,5 +1,5 @@
 from datetime import datetime, timezone
-from sqlalchemy import String, Text, DateTime, ForeignKey, Integer
+from sqlalchemy import String, Text, DateTime, ForeignKey, Integer, Float
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 from app.db.database import Base
 
@@ -39,3 +39,16 @@ class Memory(Base):
     created_at: Mapped[datetime] = mapped_column(DateTime, default=lambda: datetime.now(timezone.utc))
 
     session: Mapped["Session"] = relationship(back_populates="memories")
+
+
+class ApiLog(Base):
+    __tablename__ = "api_logs"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    session_id: Mapped[str | None] = mapped_column(ForeignKey("sessions.id", ondelete="SET NULL"), nullable=True)
+    model: Mapped[str] = mapped_column(String)
+    request_json: Mapped[str] = mapped_column(Text)   # JSON: messages array
+    response_text: Mapped[str | None] = mapped_column(Text, nullable=True)
+    error: Mapped[str | None] = mapped_column(Text, nullable=True)
+    latency_ms: Mapped[float | None] = mapped_column(Float, nullable=True)
+    created_at: Mapped[datetime] = mapped_column(DateTime, default=lambda: datetime.now(timezone.utc))