feat: Meeting Assistant MVP - Complete implementation

Enterprise Meeting Knowledge Management System with:

Backend (FastAPI):
- Authentication proxy with JWT (pj-auth-api integration)
- MySQL database with 4 tables (users, meetings, conclusions, actions)
- Meeting CRUD with system code generation (C-YYYYMMDD-XX, A-YYYYMMDD-XX)
- Dify LLM integration for AI summarization
- Excel export with openpyxl
- 20 unit tests (all passing)

Client (Electron):
- Login page with company auth
- Meeting list with create/delete
- Meeting detail with real-time transcription
- Editable transcript textarea (single block, easy editing)
- AI summarization with conclusions/action items
- 5-second segment recording (efficient for long meetings)

Sidecar (Python):
- faster-whisper medium model with int8 quantization
- ONNX Runtime VAD (lightweight, ~20MB vs PyTorch ~2GB)
- Chinese punctuation processing
- OpenCC for Traditional Chinese conversion
- Anti-hallucination parameters
- Auto-cleanup of temp audio files

OpenSpec:
- add-meeting-assistant-mvp (47 tasks, archived)
- add-realtime-transcription (29 tasks, archived)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

client/src/services/api.js

@@ -0,0 +1,149 @@
+const API_BASE_URL = "http://localhost:8000/api";
+
+let authToken = null;
+let tokenRefreshTimer = null;
+
+export function setToken(token) {
+  authToken = token;
+  localStorage.setItem("authToken", token);
+  scheduleTokenRefresh();
+}
+
+export function getToken() {
+  if (!authToken) {
+    authToken = localStorage.getItem("authToken");
+  }
+  return authToken;
+}
+
+export function clearToken() {
+  authToken = null;
+  localStorage.removeItem("authToken");
+  if (tokenRefreshTimer) {
+    clearTimeout(tokenRefreshTimer);
+  }
+}
+
+function scheduleTokenRefresh() {
+  // Refresh token 5 minutes before expiry (assuming 24h token)
+  const refreshIn = 23 * 60 * 60 * 1000; // 23 hours
+  if (tokenRefreshTimer) {
+    clearTimeout(tokenRefreshTimer);
+  }
+  tokenRefreshTimer = setTimeout(async () => {
+    try {
+      // Re-login would require stored credentials
+      // For now, just notify user to re-login
+      console.warn("Token expiring soon, please re-login");
+    } catch (error) {
+      console.error("Token refresh failed:", error);
+    }
+  }, refreshIn);
+}
+
+async function request(endpoint, options = {}) {
+  const url = `${API_BASE_URL}${endpoint}`;
+  const headers = {
+    "Content-Type": "application/json",
+    ...options.headers,
+  };
+
+  const token = getToken();
+  if (token) {
+    headers["Authorization"] = `Bearer ${token}`;
+  }
+
+  const response = await fetch(url, {
+    ...options,
+    headers,
+  });
+
+  if (response.status === 401) {
+    const error = await response.json();
+    if (error.detail?.error === "token_expired") {
+      clearToken();
+      window.electronAPI.navigate("login");
+      throw new Error("Session expired, please login again");
+    }
+    throw new Error(error.detail || "Unauthorized");
+  }
+
+  if (!response.ok) {
+    const error = await response.json().catch(() => ({}));
+    throw new Error(error.detail || `HTTP error ${response.status}`);
+  }
+
+  // Handle blob responses for export
+  if (options.responseType === "blob") {
+    return response.blob();
+  }
+
+  return response.json();
+}
+
+// Auth API
+export async function login(email, password) {
+  const data = await request("/login", {
+    method: "POST",
+    body: JSON.stringify({ email, password }),
+  });
+  setToken(data.token);
+  localStorage.setItem("userEmail", data.email);
+  localStorage.setItem("userRole", data.role);
+  return data;
+}
+
+export async function getMe() {
+  return request("/me");
+}
+
+// Meetings API
+export async function getMeetings() {
+  return request("/meetings");
+}
+
+export async function getMeeting(id) {
+  return request(`/meetings/${id}`);
+}
+
+export async function createMeeting(meeting) {
+  return request("/meetings", {
+    method: "POST",
+    body: JSON.stringify(meeting),
+  });
+}
+
+export async function updateMeeting(id, meeting) {
+  return request(`/meetings/${id}`, {
+    method: "PUT",
+    body: JSON.stringify(meeting),
+  });
+}
+
+export async function deleteMeeting(id) {
+  return request(`/meetings/${id}`, {
+    method: "DELETE",
+  });
+}
+
+export async function updateActionItem(meetingId, actionId, data) {
+  return request(`/meetings/${meetingId}/actions/${actionId}`, {
+    method: "PUT",
+    body: JSON.stringify(data),
+  });
+}
+
+// AI API
+export async function summarizeTranscript(transcript) {
+  return request("/ai/summarize", {
+    method: "POST",
+    body: JSON.stringify({ transcript }),
+  });
+}
+
+// Export API
+export async function exportMeeting(id) {
+  return request(`/meetings/${id}/export`, {
+    responseType: "blob",
+  });
+}