feat: HR Portal - Complete Multi-Tenant System with Redis Session Storage

Major Features:
- ✅ Multi-tenant architecture (tenant isolation)
- ✅ Employee CRUD with lifecycle management (onboarding/offboarding)
- ✅ Department tree structure with email domain management
- ✅ Company info management (single-record editing)
- ✅ System functions CRUD (permission management)
- ✅ Email account management (multi-account per employee)
- ✅ Keycloak SSO integration (auth.lab.taipei)
- ✅ Redis session storage (10.1.0.254:6379)
  - Solves Cookie 4KB limitation
  - Cross-system session sharing
  - Sliding expiration (8 hours)
  - Automatic token refresh

Technical Stack:
Backend:
- FastAPI + SQLAlchemy
- PostgreSQL 16 (10.1.0.20:5433)
- Keycloak Admin API integration
- Docker Mailserver integration (SSH)
- Alembic migrations

Frontend:
- Next.js 14 (App Router)
- NextAuth 4 with Keycloak Provider
- Redis session storage (ioredis)
- Tailwind CSS

Infrastructure:
- Redis 7 (10.1.0.254:6379) - Session + Cache
- Keycloak 26.1.0 (auth.lab.taipei)
- Docker Mailserver (10.1.0.254)

Architecture Highlights:
- Session管理由 Keycloak + Redis 統一控制
- 支援多系統 (HR/WebMail/Calendar/Drive/Office) 共享 session
- Token 自動刷新,異質服務整合
- 未來可無縫遷移到雲端

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

scripts/SETUP-SSH-KEY-EASY.txt

@@ -0,0 +1,43 @@
+========================================
+SSH 免密碼登入設定 (超簡單版)
+========================================
+
+只需要 3 步驟,1 分鐘完成!
+
+========================================
+步驟 1: 在 Windows PowerShell 執行
+========================================
+
+# 檢查是否已有 SSH 金鑰
+if (Test-Path "$env:USERPROFILE\.ssh\id_rsa.pub") {
+    Write-Host "SSH 金鑰已存在!" -ForegroundColor Green
+    Get-Content "$env:USERPROFILE\.ssh\id_rsa.pub"
+} else {
+    Write-Host "正在生成 SSH 金鑰..." -ForegroundColor Yellow
+    ssh-keygen -t rsa -b 4096 -f "$env:USERPROFILE\.ssh\id_rsa" -N ""
+    Write-Host "金鑰生成完成!" -ForegroundColor Green
+    Get-Content "$env:USERPROFILE\.ssh\id_rsa.pub"
+}
+
+========================================
+步驟 2: 上傳公鑰到 Ubuntu Server
+========================================
+
+# 執行這一行命令 (需要輸入密碼最後一次)
+type $env:USERPROFILE\.ssh\id_rsa.pub | ssh ubuntu@10.1.0.254 "mkdir -p ~/.ssh && chmod 700 ~/.ssh && cat >> ~/.ssh/authorized_keys && chmod 600 ~/.ssh/authorized_keys && echo '========== SSH 金鑰設定完成! =========='"
+
+========================================
+步驟 3: 測試免密碼登入
+========================================
+
+# 測試 (應該不用輸入密碼)
+ssh ubuntu@10.1.0.254 "echo '免密碼登入成功! 🎉'"
+
+========================================
+完成!
+========================================
+
+之後所有操作都可以全自動執行了!
+
+回來告訴我「設定完成」,我就能自動幫你執行所有任務! 🚀
+========================================