feat: implement full-stack TaskPilot scheduler

backend/tests/api.rs

@@ -0,0 +1,74 @@
+use axum::{
+    body::Body,
+    http::{Request, StatusCode},
+};
+use http_body_util::BodyExt;
+use serde_json::Value;
+use tempfile::TempDir;
+use tower::ServiceExt;
+
+async fn test_app() -> (axum::Router, TempDir) {
+    let temp_dir = TempDir::new().expect("temporary directory should be created");
+    let pool = task_pilot_backend::database::connect("sqlite::memory:")
+        .await
+        .expect("test database should initialize");
+    let app = task_pilot_backend::app(pool, temp_dir.path().join("logs"))
+        .await
+        .expect("test app should start");
+    (app, temp_dir)
+}
+
+#[tokio::test]
+async fn health_endpoint_returns_service_metadata() {
+    let (app, _temp_dir) = test_app().await;
+    let response = app
+        .oneshot(
+            Request::builder()
+                .uri("/api/v1/health")
+                .body(Body::empty())
+                .expect("request should build"),
+        )
+        .await
+        .expect("router should respond");
+
+    assert_eq!(response.status(), StatusCode::OK);
+
+    let body = response
+        .into_body()
+        .collect()
+        .await
+        .expect("response body should be readable")
+        .to_bytes();
+    let json: Value = serde_json::from_slice(&body).expect("response should be JSON");
+
+    assert_eq!(json["status"], "ok");
+    assert_eq!(json["service"], "task-pilot-backend");
+    assert_eq!(json["version"], env!("CARGO_PKG_VERSION"));
+}
+
+#[tokio::test]
+async fn openapi_endpoint_describes_health_api() {
+    let (app, _temp_dir) = test_app().await;
+    let response = app
+        .oneshot(
+            Request::builder()
+                .uri("/api/v1/openapi.json")
+                .body(Body::empty())
+                .expect("request should build"),
+        )
+        .await
+        .expect("router should respond");
+
+    assert_eq!(response.status(), StatusCode::OK);
+
+    let body = response
+        .into_body()
+        .collect()
+        .await
+        .expect("response body should be readable")
+        .to_bytes();
+    let json: Value = serde_json::from_slice(&body).expect("response should be JSON");
+
+    assert_eq!(json["info"]["title"], "TaskPilot API");
+    assert!(json["paths"]["/api/v1/health"]["get"].is_object());
+}