[9ef46be7] feat(prompter): implement Prompter page, nav entry, chat UI, and task creation wiring (#78) (#79)

- Add Task Assistant nav entry (Sparkles icon) to sidebar between Kanban and Projects
- Create lib/api/prompter.ts with createSession, sendMessage, getDraft API functions
- Create hooks/use-prompter.ts with 6-state machine (empty→chatting→draft_preview→review_modal→launching→success)
- Create ChatMessages with auto-scroll, user/assistant/error rendering, inline DraftProposalCard
- Create ChatComposer with Enter-to-send and Shift+Enter for newline
- Create DraftProposalCard with title, description, acceptance criteria, metadata badges, Keep Chatting/Review & Confirm actions
- Create ConfirmDialog (Radix Dialog, no form element) with MarkdownEditor, AcceptanceCriteriaEditor, metadata selects, warning banner, disabled Confirm & Launch until valid
- Create SuccessCard with task title, team, View Task link, Start Another button
- Create /prompter route page composing all components via usePrompter hook
- TypeScript and ESLint pass with zero errors

Co-authored-by: Frontend Developer 2 <fe-dev-2@agents.roboco.dev>

panel/src/lib/api/prompter.ts

@@ -0,0 +1,65 @@
+import api from "./client";
+import type { Team, TaskType, Complexity } from "@/types";
+
+// ---------------------------------------------------------------------------
+// Types
+// ---------------------------------------------------------------------------
+
+export interface DraftProposal {
+  title: string;
+  description: string;
+  acceptance_criteria: string[];
+  team: Team;
+  priority?: number;
+  task_type?: TaskType;
+  estimated_complexity?: Complexity;
+}
+
+export interface ChatResponse {
+  reply: string;
+  draft?: DraftProposal | null;
+  session_id: string;
+}
+
+export interface CreateSessionResponse {
+  session_id: string;
+}
+
+// ---------------------------------------------------------------------------
+// API functions
+// ---------------------------------------------------------------------------
+
+export const prompterApi = {
+  /**
+   * Create a new prompter session, returning a session ID.
+   */
+  createSession: async (): Promise<CreateSessionResponse> => {
+    const { data } = await api.post<CreateSessionResponse>("/prompter/sessions");
+    return data;
+  },
+
+  /**
+   * Send a chat message in an existing session.
+   * Returns the assistant reply and, if ready, a draft task proposal.
+   */
+  sendMessage: async (
+    sessionId: string,
+    message: string
+  ): Promise<ChatResponse> => {
+    const { data } = await api.post<ChatResponse>(
+      `/prompter/sessions/${sessionId}/chat`,
+      { message }
+    );
+    return data;
+  },
+
+  /**
+   * Fetch the current draft for a session (if the LLM has produced one).
+   */
+  getDraft: async (sessionId: string): Promise<DraftProposal | null> => {
+    const { data } = await api.get<{ draft: DraftProposal | null }>(
+      `/prompter/sessions/${sessionId}/draft`
+    );
+    return data.draft;
+  },
+};