Fix ALB listener default action, auto-import numberOfAzs, and correct docs

- Fix HTTP listener in spicy-alb.ts missing default action when no certificate
  is provided, which would cause CDK synth to fail
- Auto-import numberOfAzs from VPC stack exports (NumberOfAZs) in cluster,
  service, and ALB stacks when not provided via context
- Fix CDK_SYNTH_EXAMPLES.md ALB examples using raw vpcId/subnetIds that don't
  match the actual fromContext() implementation (requires clusterName)
- Fix docs overstating "only clusterName required" to list actual required params
- Remove package-lock.json and add to .gitignore (project uses pnpm)

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

resources/lib/stacks/spicy-ecs-cluster-stack.ts

@@ -243,10 +243,18 @@ export class SpicyEcsClusterStack extends cdk.Stack {
         'vpcStackName is required. Provide vpcStackName to import all VPC details from VPC stack exports.'
       );
     }
+    // numberOfAzs: use context value if provided, otherwise auto-import from VPC stack export
     const numberOfAzsRaw = app.node.tryGetContext('numberOfAzs');
-    const numberOfAzs = numberOfAzsRaw ? parseInt(numberOfAzsRaw, 10) : NaN;
+    let numberOfAzs: number;
+    if (numberOfAzsRaw) {
+      numberOfAzs = parseInt(numberOfAzsRaw, 10);
+    } else {
+      // Auto-import from VPC stack export
+      const imported = cdk.Fn.importValue(`${vpcStackName}-NumberOfAZs`).toString();
+      numberOfAzs = parseInt(imported, 10);
+    }
     if (!numberOfAzs || Number.isNaN(numberOfAzs)) {
-      throw new Error('numberOfAzs is required in context (2-4) to import subnets from the VPC stack.');
+      throw new Error('numberOfAzs is required (2-4). Provide via context or ensure VPC stack exports NumberOfAZs.');
     }
 
     // Tags