feat: add hub runtime and extension contract

hub_core/runtime/app.py

@@ -0,0 +1,54 @@
+from __future__ import annotations
+
+from fastapi import FastAPI, Response, status
+
+from hub_core import __version__
+from hub_core.runtime.config import RuntimeSettings
+from hub_core.runtime.models import HealthResponse, ReadinessResponse
+from hub_core.runtime.ports import create_ports_router
+from hub_core.runtime.store import InMemoryPortStore, PortStore
+from hub_core.runtime.validation import ContractValidator
+
+
+def create_app(
+    *,
+    settings: RuntimeSettings | None = None,
+    port_store: PortStore | None = None,
+) -> FastAPI:
+    resolved_settings = settings or RuntimeSettings.from_env()
+    resolved_store = port_store or _create_store(resolved_settings)
+
+    app = FastAPI(
+        title="Hub Core Runtime",
+        version=__version__,
+        description="HelixForge hub framework and named-port runtime.",
+    )
+    app.state.settings = resolved_settings
+    app.state.port_store = resolved_store
+    app.state.contract_validator = ContractValidator()
+
+    @app.get("/healthz", response_model=HealthResponse, tags=["system"])
+    async def healthz() -> HealthResponse:
+        return HealthResponse(version=__version__)
+
+    @app.get("/readyz", response_model=ReadinessResponse, tags=["system"])
+    async def readyz(response: Response) -> ReadinessResponse:
+        ready = resolved_settings.is_ready(resolved_store.backend_name)
+        if not ready:
+            response.status_code = status.HTTP_503_SERVICE_UNAVAILABLE
+        return ReadinessResponse(
+            status="ok" if ready else "degraded",
+            checks=resolved_settings.readiness_checks(resolved_store.backend_name),
+        )
+
+    app.include_router(create_ports_router())
+    return app
+
+
+def _create_store(settings: RuntimeSettings) -> PortStore:
+    if settings.backend == "memory":
+        return InMemoryPortStore()
+    raise RuntimeError(f"Unsupported HUB_CORE_BACKEND '{settings.backend}'")
+
+
+app = create_app()