feat: reorganize agent detail tabs and add Prompts tab

Rearrange tabs to: Dashboard, Prompts, Skills, Configuration, Budget.
Move Prompt Template out of Configuration into a dedicated Prompts tab
with its own save/cancel flow and dirty tracking.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

ui/src/components/AgentConfigForm.tsx

@@ -65,6 +65,8 @@ type AgentConfigFormProps = {
   onSaveActionChange?: (save: (() => void) | null) => void;
   onCancelActionChange?: (cancel: (() => void) | null) => void;
   hideInlineSave?: boolean;
+  /** Hide the prompt template field from the Identity section (used when it's shown in a separate Prompts tab). */
+  hidePromptTemplate?: boolean;
   /** "cards" renders each section as heading + bordered card (for settings pages). Default: "inline" (border-b dividers). */
   sectionLayout?: "inline" | "cards";
 } & (
@@ -473,7 +475,7 @@ export function AgentConfigForm(props: AgentConfigFormProps) {
                 }}
               />
             </Field>
-            {isLocal && (
+            {isLocal && !props.hidePromptTemplate && (
               <>
                 <Field label="Prompt Template" hint={help.promptTemplate}>
                   <MarkdownEditor