feat(ui,api,admin): sveltekit admin spa, usage by day/agent/conversation/model, rate limits, memory tree, turn snapshot

src/beaver_gateway/storage/models.py

@@ -319,6 +319,39 @@ class Usage(SQLModel, table=True):
     cost_usd: float | None = Field(default=None)
     duration_ms: int | None = Field(default=None)
     num_turns: int | None = Field(default=None)
+    model_usage: dict[str, Any] | None = Field(
+        default=None,
+        sa_column=Column(JSON().with_variant(JSONB(), "postgresql"), nullable=True),
+    )
+
+
+class RateLimit(SQLModel, table=True):
+    """One ``RateLimitEvent`` from the SDK; the newest row per ``window`` is the state.
+
+    The quota is per subscription, not per agent or conversation - the row
+    only remembers which session reported it.
+    """
+
+    __tablename__ = "rate_limits"
+
+    id: int | None = Field(default=None, primary_key=True)
+    ts: datetime = Field(default_factory=_utcnow, index=True)
+    window: str = Field(index=True)
+    status: str
+    utilization: float | None = Field(default=None)
+    resets_at: datetime | None = Field(default=None)
+    overage_status: str | None = Field(default=None)
+    overage_resets_at: datetime | None = Field(default=None)
+    agent_name: str | None = Field(default=None)
+    session_id: str | None = Field(default=None)
+    raw: dict[str, Any] = Field(
+        default_factory=dict,
+        sa_column=Column(
+            JSON().with_variant(JSONB(), "postgresql"),
+            nullable=False,
+            server_default=text("'{}'"),
+        ),
+    )
 
 
 __all__ = [
@@ -328,6 +361,7 @@ __all__ = [
     "ConversationMessage",
     "Delivery",
     "InjectQueueItem",
+    "RateLimit",
     "Schedule",
     "TelegramUpdate",
     "Token",