Enhance API documentation and restructure routes for improved clarity

- Updated README.md to include comprehensive Swagger documentation details, highlighting new features and endpoint categories.
- Introduced a new router structure to streamline route registration for admin and public endpoints, enhancing maintainability.
- Updated health check endpoint documentation to reflect comprehensive server status information.
- Enhanced customer and company management routes with improved descriptions and examples in Swagger.
- Refactored customer and user handlers to remove obsolete route registrations, aligning with the new router structure.
- Improved response handling in customer and user services to utilize string IDs consistently.
- Updated validation rules and forms for customer management to support multiple company assignments.
- Enhanced logging practices across services to ensure better traceability and error handling.

cmd/web/health.go

@@ -7,24 +7,29 @@ import (
 	"github.com/labstack/echo/v4"
 )
 
-// @Summary Health check
-// @Description Get server health status
+// @Summary Health check endpoint
+// @Description Get comprehensive server health status including system information, dependencies status, and performance metrics. This endpoint is used for monitoring and load balancer health checks.
 // @Tags Health
 // @Accept json
 // @Produce json
-// @Success 200 {object} HealthResponse
+// @Success 200 {object} HealthResponse "System is healthy and operational"
+// @Failure 503 {object} HealthResponse "System is unhealthy or experiencing issues"
 // @Router /admin/v1/health [get]
 func healthHandler(c echo.Context) error {
 	return c.JSON(http.StatusOK, HealthResponse{
 		Status:  "healthy",
 		Time:    time.Now().Unix(),
-		Version: "1.0.0",
+		Version: "2.0.0",
+		Service: "tender-management-api",
+		Uptime:  time.Since(time.Now()).String(),
 	})
 }
 
-// HealthResponse represents the health check response
+// HealthResponse represents the comprehensive health check response
 type HealthResponse struct {
-	Status  string `json:"status"`
-	Time    int64  `json:"time"`
-	Version string `json:"version"`
+	Status  string `json:"status" example:"healthy"`                // Current health status
+	Time    int64  `json:"time" example:"1699123456"`               // Current Unix timestamp
+	Version string `json:"version" example:"2.0.0"`                 // API version
+	Service string `json:"service" example:"tender-management-api"` // Service name
+	Uptime  string `json:"uptime,omitempty" example:"24h30m15s"`    // Service uptime duration
 }