feat: add foreign key constraints and metrics for blockchain node

apps/pool-hub/src/poolhub/app/schemas.py

@@ -0,0 +1,40 @@
+from __future__ import annotations
+
+from typing import Any, Dict, List, Optional
+
+from pydantic import BaseModel, Field
+
+
+class MatchRequestPayload(BaseModel):
+    job_id: str
+    requirements: Dict[str, Any] = Field(default_factory=dict)
+    hints: Dict[str, Any] = Field(default_factory=dict)
+    top_k: int = Field(default=1, ge=1, le=50)
+
+
+class MatchCandidate(BaseModel):
+    miner_id: str
+    addr: str
+    proto: str
+    score: float
+    explain: Optional[str] = None
+    eta_ms: Optional[int] = None
+    price: Optional[float] = None
+
+
+class MatchResponse(BaseModel):
+    job_id: str
+    candidates: List[MatchCandidate]
+
+
+class HealthResponse(BaseModel):
+    status: str
+    db: bool
+    redis: bool
+    miners_online: int
+    db_error: Optional[str] = None
+    redis_error: Optional[str] = None
+
+
+class MetricsResponse(BaseModel):
+    detail: str = "Prometheus metrics output"