fix(vscode): stop trimming edit mode fields on every keystroke

Removes .trim() from onChange handlers for description, prompt, and
model fields so spaces can be typed without being stripped. The create
mode form still trims on submit which is correct for one-shot actions.

packages/kilo-vscode/webview-ui/src/components/settings/AgentBehaviourTab.tsx

@@ -446,7 +446,7 @@ const AgentBehaviourTab: Component = () => {
             <TextField
               value={currentAgentConfig().description ?? ""}
               placeholder={language.t("settings.agentBehaviour.createMode.description.placeholder")}
-              onChange={(val) => updateAgentConfig(name, { description: val.trim() || undefined })}
+              onChange={(val) => updateAgentConfig(name, { description: val || undefined })}
             />
           </Card>
         </Show>
@@ -462,7 +462,7 @@ const AgentBehaviourTab: Component = () => {
             value={currentAgentConfig().prompt ?? ""}
             placeholder={language.t("settings.agentBehaviour.createMode.prompt.placeholder")}
             multiline
-            onChange={(val) => updateAgentConfig(name, { prompt: val.trim() || undefined })}
+            onChange={(val) => updateAgentConfig(name, { prompt: val || undefined })}
           />
         </Card>
 
@@ -478,7 +478,7 @@ const AgentBehaviourTab: Component = () => {
               placeholder="e.g. anthropic/claude-sonnet-4-20250514"
               onChange={(val) =>
                 updateAgentConfig(name, {
-                  model: val.trim() || undefined,
+                  model: val || undefined,
                 })
               }
             />