feat: Implement announcements (#1204)

* feat: Implement announcements

Fixes #1203

* Remove unnecessary code

* Fix new announcement test

* Update web/app/src/views/Home.vue

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Remove useless garbage

* Require announcement timestamp

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

api/config.go

@@ -1,14 +1,17 @@
 package api
 
 import (
+	"encoding/json"
 	"fmt"
 
+	"github.com/TwiN/gatus/v5/config"
 	"github.com/TwiN/gatus/v5/security"
 	"github.com/gofiber/fiber/v2"
 )
 
 type ConfigHandler struct {
 	securityConfig *security.Config
+	config         *config.Config
 }
 
 func (handler ConfigHandler) GetConfig(c *fiber.Ctx) error {
@@ -18,8 +21,24 @@ func (handler ConfigHandler) GetConfig(c *fiber.Ctx) error {
 		hasOIDC = handler.securityConfig.OIDC != nil
 		isAuthenticated = handler.securityConfig.IsAuthenticated(c)
 	}
-	// Return the config
+
+	// Prepare response with announcements
+	response := map[string]interface{}{
+		"oidc":          hasOIDC,
+		"authenticated": isAuthenticated,
+	}
+	// Add announcements if available, otherwise use empty slice
+	if handler.config != nil && handler.config.Announcements != nil && len(handler.config.Announcements) > 0 {
+		response["announcements"] = handler.config.Announcements
+	} else {
+		response["announcements"] = []interface{}{}
+	}
+
+	// Return the config as JSON
 	c.Set("Content-Type", "application/json")
-	return c.Status(200).
-		SendString(fmt.Sprintf(`{"oidc":%v,"authenticated":%v}`, hasOIDC, isAuthenticated))
+	responseBytes, err := json.Marshal(response)
+	if err != nil {
+		return c.Status(500).SendString(fmt.Sprintf(`{"error":"Failed to marshal response: %s"}`, err.Error()))
+	}
+	return c.Status(200).Send(responseBytes)
 }