fix: use single-quoted bash -c in rate limit tests

The failing tests used bash -c "${script}" (double quotes), which caused
bash to interpret inner double quotes in the curl commands, garbling the
HTTP headers and JSON data. Switch to bash -c '${script}' (single quotes)
and use escaped double quotes for JSON data, matching the pattern used by
the passing tests.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Mossaka

tests/integration/api-proxy-rate-limit.test.ts

@@ -61,13 +61,13 @@ describe('API Proxy Rate Limiting', () => {
     // Set RPM=1, make 2 requests quickly — second should get 429 with Retry-After
     const script = [
       // First request consumes the limit
-      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}' > /dev/null`,
+      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}" > /dev/null`,
       // Second request should be rate limited — capture headers
-      `curl -s -i -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}'`,
+      `curl -s -i -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}"`,
     ].join(' && ');
 
     const result = await runner.runWithSudo(
-      `bash -c "${script}"`,
+      `bash -c '${script}'`,
       {
         allowDomains: ['api.anthropic.com'],
         enableApiProxy: true,
@@ -112,12 +112,12 @@ describe('API Proxy Rate Limiting', () => {
   test('should include X-RateLimit headers in 429 response', async () => {
     // Set low RPM to guarantee 429, then check for X-RateLimit-* headers
     const script = [
-      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}' > /dev/null`,
-      `curl -s -i -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}'`,
+      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}" > /dev/null`,
+      `curl -s -i -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}"`,
     ].join(' && ');
 
     const result = await runner.runWithSudo(
-      `bash -c "${script}"`,
+      `bash -c '${script}'`,
       {
         allowDomains: ['api.anthropic.com'],
         enableApiProxy: true,
@@ -172,13 +172,13 @@ describe('API Proxy Rate Limiting', () => {
     // Set a custom RPM and verify it appears in the health endpoint rate_limits
     const script = [
       // Make one request to create provider state in the limiter
-      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}' > /dev/null`,
+      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}" > /dev/null`,
       // Check health for rate limit config
       `curl -s http://${API_PROXY_IP}:10000/health`,
     ].join(' && ');
 
     const result = await runner.runWithSudo(
-      `bash -c "${script}"`,
+      `bash -c '${script}'`,
       {
         allowDomains: ['api.anthropic.com'],
         enableApiProxy: true,
@@ -203,15 +203,15 @@ describe('API Proxy Rate Limiting', () => {
     // Trigger rate limiting, then check /metrics for rate_limit_rejected_total
     const script = [
       // Make 3 rapid requests with RPM=1 to trigger at least one 429
-      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}' > /dev/null`,
-      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}' > /dev/null`,
-      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d '{"model":"test"}' > /dev/null`,
+      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}" > /dev/null`,
+      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}" > /dev/null`,
+      `curl -s -X POST http://${API_PROXY_IP}:10001/v1/messages -H "Content-Type: application/json" -d "{\\"model\\":\\"test\\"}" > /dev/null`,
       // Check metrics
       `curl -s http://${API_PROXY_IP}:10000/metrics`,
     ].join(' && ');
 
     const result = await runner.runWithSudo(
-      `bash -c "${script}"`,
+      `bash -c '${script}'`,
       {
         allowDomains: ['api.anthropic.com'],
         enableApiProxy: true,