feat: add mission control about endpoint

Expose mission-control version metadata from /about for the UI version display. Return the binary app version and the Helm chart version when FLANKSOURCE_CHART_VERSION is available.

Author: adityathebe

echo/serve.go

@@ -10,6 +10,7 @@ import (
 	"net"
 	"net/http"
 	"net/url"
+	"os"
 	"strings"
 	"time"
 
@@ -150,6 +151,13 @@ func New(ctx context.Context) *echov4.Echo {
 		return c.String(http.StatusOK, "OK")
 	})
 
+	e.GET("/about", func(c echov4.Context) error {
+		return c.JSON(http.StatusOK, map[string]string{
+			"appVersion":   api.BuildVersion,
+			"chartVersion": os.Getenv("FLANKSOURCE_CHART_VERSION"),
+		})
+	})
+
 	personController := PersonController{kratos: auth.NewAPIClient(auth.KratosAPI)}
 	e.POST("/people/update", personController.UpdatePerson, rbac.Authorization(policy.ObjectPeople, policy.ActionUpdate))
 	e.DELETE("/people/:id", personController.DeletePerson, rbac.Authorization(policy.ObjectPeople, policy.ActionDelete))