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/check-postgres.ps1

@@ -0,0 +1,102 @@
+# PostgreSQL Connection Check Script
+# This script checks if PostgreSQL is accessible and ready for HR Portal setup
+
+$ErrorActionPreference = "Continue"
+
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host "  PostgreSQL Connection Check" -ForegroundColor Cyan
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host ""
+
+# Configuration
+$POSTGRES_HOST = "10.1.0.254"
+$POSTGRES_PORT = 5432
+
+# Step 1: Test Network Connectivity
+Write-Host "[1/4] Testing network connectivity..." -ForegroundColor Yellow
+try {
+    $tcpResult = Test-NetConnection -ComputerName $POSTGRES_HOST -Port $POSTGRES_PORT -WarningAction SilentlyContinue
+
+    if ($tcpResult.TcpTestSucceeded) {
+        Write-Host "  [OK] Port $POSTGRES_PORT is accessible on $POSTGRES_HOST" -ForegroundColor Green
+    } else {
+        Write-Host "  [FAIL] Cannot reach port $POSTGRES_PORT on $POSTGRES_HOST" -ForegroundColor Red
+        Write-Host "  Please check if PostgreSQL container is running" -ForegroundColor Yellow
+        exit 1
+    }
+} catch {
+    Write-Host "  [ERROR] Network test failed: $($_.Exception.Message)" -ForegroundColor Red
+    exit 1
+}
+
+Write-Host ""
+
+# Step 2: Check Docker Containers
+Write-Host "[2/4] Checking Docker containers on remote host..." -ForegroundColor Yellow
+try {
+    $containers = ssh ubuntu@$POSTGRES_HOST "docker ps --format 'table {{.Names}}\t{{.Image}}\t{{.Status}}' | grep postgres"
+
+    if ($LASTEXITCODE -eq 0) {
+        Write-Host "  [OK] PostgreSQL containers found:" -ForegroundColor Green
+        Write-Host "  $containers" -ForegroundColor White
+    } else {
+        Write-Host "  [WARNING] No PostgreSQL containers found or SSH failed" -ForegroundColor Yellow
+        Write-Host "  This is not critical if you can connect to database" -ForegroundColor Gray
+    }
+} catch {
+    Write-Host "  [WARNING] Could not check containers: $($_.Exception.Message)" -ForegroundColor Yellow
+}
+
+Write-Host ""
+
+# Step 3: Test Database Connection
+Write-Host "[3/4] Testing database connection..." -ForegroundColor Yellow
+Write-Host "  Please enter postgres password when prompted" -ForegroundColor Gray
+
+try {
+    # Test connection to postgres default database
+    $testQuery = "SELECT version();"
+    $result = ssh ubuntu@$POSTGRES_HOST "docker exec -i postgres psql -U postgres -c `"$testQuery`"" 2>&1
+
+    if ($LASTEXITCODE -eq 0) {
+        Write-Host "  [OK] Successfully connected to PostgreSQL" -ForegroundColor Green
+        Write-Host "  Version info:" -ForegroundColor Gray
+        Write-Host "  $result" -ForegroundColor White
+    } else {
+        Write-Host "  [FAIL] Could not connect to PostgreSQL" -ForegroundColor Red
+        Write-Host "  Error: $result" -ForegroundColor Red
+        exit 1
+    }
+} catch {
+    Write-Host "  [ERROR] Connection test failed: $($_.Exception.Message)" -ForegroundColor Red
+    exit 1
+}
+
+Write-Host ""
+
+# Step 4: Check if hr_portal database exists
+Write-Host "[4/4] Checking for existing hr_portal database..." -ForegroundColor Yellow
+
+try {
+    $dbCheck = ssh ubuntu@$POSTGRES_HOST "docker exec -i postgres psql -U postgres -lqt | cut -d '|' -f 1 | grep -w hr_portal" 2>&1
+
+    if ($LASTEXITCODE -eq 0) {
+        Write-Host "  [INFO] hr_portal database already exists" -ForegroundColor Yellow
+        Write-Host "  You may want to drop it before running setup-db-simple.ps1" -ForegroundColor Gray
+        Write-Host "  Command: docker exec postgres psql -U postgres -c 'DROP DATABASE hr_portal;'" -ForegroundColor Gray
+    } else {
+        Write-Host "  [OK] hr_portal database does not exist (ready for setup)" -ForegroundColor Green
+    }
+} catch {
+    Write-Host "  [INFO] Could not check database: $($_.Exception.Message)" -ForegroundColor Gray
+}
+
+Write-Host ""
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host "  Check completed!" -ForegroundColor Cyan
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host ""
+Write-Host "Next steps:" -ForegroundColor Yellow
+Write-Host "  1. Run setup-db-simple.ps1 to create hr_portal database" -ForegroundColor White
+Write-Host "  2. Execute test data insertion if needed" -ForegroundColor White
+Write-Host ""