feat: Health Check 엔드포인트 구현 (#24)

Reviewed-on: https://git.ipstein.myds.me/SPMS/SPMS_API/pulls/25

SPMS.API/Controllers/PublicController.cs

@@ -0,0 +1,54 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+using SPMS.Domain.Common;
+using SPMS.Infrastructure;
+
+namespace SPMS.API.Controllers;
+
+[ApiController]
+[Route("v1/out")]
+[AllowAnonymous]
+public class PublicController : ControllerBase
+{
+    private readonly AppDbContext _dbContext;
+
+    public PublicController(AppDbContext dbContext)
+    {
+        _dbContext = dbContext;
+    }
+
+    [HttpPost("health")]
+    public async Task<IActionResult> HealthCheckAsync()
+    {
+        var checks = new Dictionary<string, object>();
+        var allHealthy = true;
+
+        // 1. MariaDB 연결 확인
+        try
+        {
+            await _dbContext.Database.ExecuteSqlRawAsync("SELECT 1");
+            checks["database"] = new { status = "healthy" };
+        }
+        catch (Exception ex)
+        {
+            checks["database"] = new { status = "unhealthy", error = ex.Message };
+            allHealthy = false;
+        }
+
+        // 2. Redis 연결 확인 (Phase 2에서 구현 예정)
+        checks["redis"] = new { status = "not_configured" };
+
+        // 3. RabbitMQ 연결 확인 (Phase 2에서 구현 예정)
+        checks["rabbitmq"] = new { status = "not_configured" };
+
+        if (allHealthy)
+        {
+            return Ok(ApiResponse<object>.Success(checks));
+        }
+
+        return StatusCode(503, ApiResponse<object>.Fail(
+            ErrorCodes.InternalError,
+            "하나 이상의 서비스에 문제가 있습니다."));
+    }
+}