Migrate frontend to Svelte 5 runes semantics

frontend/src/components/git/BranchSelector.svelte

@@ -6,12 +6,12 @@
 @RELATION:  CALLS -> gitService.getBranches
 @RELATION:  CALLS -> gitService.checkoutBranch
 @RELATION:  CALLS -> gitService.createBranch
-@RELATION:  DISPATCHES -> change
+@RELATION:  BINDS_TO -> onchange
 -->
 
 <script>
     // [SECTION: IMPORTS]
-    import { onMount, createEventDispatcher } from 'svelte';
+    import { onMount } from 'svelte';
     import { gitService } from '../../services/gitService';
     import { addToast as toast } from '../../lib/toasts.js';
     import { t } from '../../lib/i18n';
@@ -23,6 +23,7 @@
     dashboardId,
     envId = null,
     currentBranch = $bindable('main'),
+    onchange = () => {},
   } = $props();
 
     // [/SECTION]
@@ -33,9 +34,6 @@
     let showCreate = $state(false);
     let newBranchName = $state('');
     // [/SECTION]
-
-    const dispatch = createEventDispatcher();
-
     // [DEF:onMount:Function]
     /**
      * @purpose Load branches when component is mounted.
@@ -83,14 +81,14 @@
     /**
      * @purpose Переключает текущую ветку.
      * @param {string} branchName - Имя ветки.
-     * @post currentBranch обновлен, событие отправлено.
+     * @post currentBranch обновлен, родительский callback вызван.
      */
     async function handleCheckout(branchName) {
         console.log(`[BranchSelector][Action] Checking out branch ${branchName}`);
         try {
             await gitService.checkoutBranch(dashboardId, branchName, envId);
             currentBranch = branchName;
-            dispatch('change', { branch: branchName });
+            onchange({ branch: branchName });
             toast($t.git?.switched_to?.replace('{branch}', branchName), 'success');
             console.log(`[BranchSelector][Coherence:OK] Checked out ${branchName}`);
         } catch (e) {