fix: resolve Svelte 5 'props_invalid_value' error by removing defaults from $bindable props

Binding to an undefined value when a $bindable prop has a default fallback causes a runtime error in Svelte 5 runes mode. Defaults are now applied within the component logic.

src/lib/ae_elements/AE_AITools.svelte

@@ -39,18 +39,26 @@
     let { 
         content, 
         summary = $bindable(),
-        model = $bindable('dgrzone-deepseek-8b-quick'),
-        baseUrl = $bindable('https://ai.dgrzone.com/api'),
-        token = $bindable(''),
-        systemPrompt = $bindable('You are a helpful assistant.'),
-        maxTokens = $bindable(512),
-        temperature = $bindable(0.7),
+        model = $bindable(),
+        baseUrl = $bindable(),
+        token = $bindable(),
+        systemPrompt = $bindable(),
+        maxTokens = $bindable(),
+        temperature = $bindable(),
         onSave,
         onSyncConfig,
         buttonClass = "btn btn-sm preset-tonal-primary shadow-lg hover:scale-105 transition-all",
         log_lvl = 0 
     }: Props = $props();
 
+    // Apply defaults if undefined (Safe for Svelte 5 Runes)
+    if (model === undefined) model = 'dgrzone-deepseek-8b-quick';
+    if (baseUrl === undefined) baseUrl = 'https://ai.dgrzone.com/api';
+    if (token === undefined) token = '';
+    if (systemPrompt === undefined) systemPrompt = 'You are a helpful assistant.';
+    if (maxTokens === undefined) maxTokens = 512;
+    if (temperature === undefined) temperature = 0.7;
+
     // Internal State
     let ae_promises: any = $state(null);
     let show_modal = $state(false);

src/lib/app_components/e_app_codemirror_v5.svelte

@@ -29,7 +29,7 @@
 
     let {
         content = 'test test test test',
-        new_content = $bindable(''),
+        new_content = $bindable(),
         editorView = $bindable(), // Exposed for external control
         theme_mode = 'light',
         extensions = [],