refactor: Rename CodeMirror wrapper and fix editor buttons

Renamed Tiptap_editor to CodeMirror_wrapper and updated all usages. Renamed the wrapper file to element_codemirror_editor_wrapper.svelte. Fixed a TypeError in the CodeMirror editor buttons by using EditorSelection.range() to correctly create selection ranges.

src/lib/elements/element_codemirror_editor_wrapper.svelte

@@ -0,0 +1,21 @@
+<script lang="ts">
+    import ElementCodemirrorEditor from './element_codemirror_editor.svelte';
+    import { browser } from '$app/environment';
+
+    export let html_text: string = '';
+    export let placeholder: string = 'Type your text here...';
+    export let classes: string = '';
+</script>
+
+<div class="block w-full h-full {classes}">
+    {#if browser}
+        <ElementCodemirrorEditor
+            class="p-1 transition-all duration-1000"
+            bind:content={html_text}
+            {placeholder}
+        />
+    {:else}
+        <!-- server / prerender placeholder to avoid SSR loading CM -->
+        <div class="p-2 text-sm text-surface-600-400">Editor (client only)</div>
+    {/if}
+</div>