Fix: Make CI .env manipulation robust against missing trailing newlines (#15189)

## Problem

CI workflow started timing out on October 14, 2025 after commit
`d750df7fff` removed the trailing newline from `.env.example`.

## Root Cause

When `.env.example` lacks a trailing newline:
```bash
# Last line without newline
# CLICKHOUSE_URL=...twenty
```

And CI runs:
```bash
echo "NODE_PORT=3002" >> .env
```

Result:
```bash
# CLICKHOUSE_URL=...twentyNODE_PORT=3002  ← Commented out!
```

Server starts on default port 3000 instead of 3002, health check fails.

## Fix

1. **Restore trailing newline** to `.env.example`
2. **Make all CI `.env` operations robust** by adding `echo "" >> .env`
before appending
3. **Simplified `set_env_var`** function to always add newline first

Now works regardless of whether template files have trailing newlines.

## Files Changed

- 6 CI workflow files
- 1 .env.example file

.github/workflows/ci-breaking-changes.yaml

@@ -124,13 +124,14 @@ jobs:
       - name: Setup current branch database
         run: |
           npx nx reset:env twenty-server
-          # Function to set or update environment variable
           set_env_var() {
             local var_name="$1"
             local var_value="$2"
             local env_file="packages/twenty-server/.env"
             
-            if grep -q "^${var_name}=" "$env_file"; then
+            echo "" >> "$env_file"
+            
+            if grep -q "^${var_name}=" "$env_file" 2>/dev/null; then
               sed -i "s|^${var_name}=.*|${var_name}=${var_value}|" "$env_file"
             else
               echo "${var_name}=${var_value}" >> "$env_file"
@@ -276,13 +277,14 @@ jobs:
       - name: Setup main branch database
         run: |
           npx nx reset:env twenty-server
-          # Function to set or update environment variable
           set_env_var() {
             local var_name="$1"
             local var_value="$2"
             local env_file="packages/twenty-server/.env"
             
-            if grep -q "^${var_name}=" "$env_file"; then
+            echo "" >> "$env_file"
+            
+            if grep -q "^${var_name}=" "$env_file" 2>/dev/null; then
               sed -i "s|^${var_name}=.*|${var_name}=${var_value}|" "$env_file"
             else
               echo "${var_name}=${var_value}" >> "$env_file"

.github/workflows/ci-cli.yaml

@@ -81,6 +81,7 @@ jobs:
       - name: Server / Append billing config to .env.test
         working-directory: packages/twenty-server
         run: |
+          echo "" >> .env.test
           echo "IS_BILLING_ENABLED=true" >> .env.test
           echo "BILLING_STRIPE_API_KEY=test-api-key" >> .env.test
           echo "BILLING_STRIPE_BASE_PLAN_PRODUCT_ID=test-base-plan-product-id" >> .env.test

.github/workflows/ci-front.yaml

@@ -140,6 +140,7 @@ jobs:
         run: |
           cd packages/twenty-front
           touch .env
+          echo "" >> .env
           echo "REACT_APP_SERVER_BASE_URL: $REACT_APP_SERVER_BASE_URL" >> .env
       - name: Publish to Chromatic
         run: npx nx run twenty-front:chromatic:ci

.github/workflows/ci-server.yaml

@@ -218,6 +218,7 @@ jobs:
         uses: ./.github/workflows/actions/yarn-install
       - name: Update .env.test for integrations tests
         run: |
+          echo "" >> .env.test
           echo "IS_BILLING_ENABLED=true" >> .env.test
           echo "BILLING_STRIPE_API_KEY=test-api-key" >> .env.test
           echo "BILLING_STRIPE_BASE_PLAN_PRODUCT_ID=test-base-plan-product-id" >> .env.test

.github/workflows/ci-test-docker-compose.yaml

@@ -33,6 +33,7 @@ jobs:
           echo "Setting up .env file..."
           cp .env.example .env
           echo "Generating secrets..."
+          echo "" >> .env
           echo "# === Randomly generated secrets ===" >>.env
           echo "APP_SECRET=$(openssl rand -base64 32)" >>.env
           echo "PGPASSWORD_SUPERUSER=$(openssl rand -hex 16)" >>.env

.github/workflows/preview-env-keepalive.yaml

@@ -37,6 +37,7 @@ jobs:
           cp packages/twenty-docker/.env.example packages/twenty-docker/.env
           
           echo "Generating secrets..."
+          echo "" >> packages/twenty-docker/.env
           echo "# === Randomly generated secrets ===" >> packages/twenty-docker/.env
           echo "APP_SECRET=$(openssl rand -base64 32)" >> packages/twenty-docker/.env
           echo "PG_DATABASE_PASSWORD=$(openssl rand -hex 16)" >> packages/twenty-docker/.env
@@ -60,6 +61,7 @@ jobs:
           # Update the SERVER_URL with the tunnel URL
           echo "Setting SERVER_URL to ${{ steps.expose-tunnel.outputs.tunnel-url }}"
           sed -i '/SERVER_URL=/d' .env
+          echo "" >> .env
           echo "SERVER_URL=${{ steps.expose-tunnel.outputs.tunnel-url }}" >> .env
           
           # Start the services