feat(scheduler): validate schedule name length (#31200)

### Issue # (if applicable)

N/A

### Reason for this change

To catch name too long errors before hitting Cloudformation.

### Description of changes

I've added a length assertion in the `Schedule` constructor against the schedule name length, the documentation on schedule name already makes it clear that there is a limit though AFAICS this isn't validated.

Also see the Cloudformation doc here: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-scheduler-schedule.html#cfn-scheduler-schedule-name.

### Description of how you validated changes

I've added a unit test.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/aws-scheduler-alpha/lib/schedule.ts

@@ -1,4 +1,4 @@
-import { Duration, IResource, Resource } from 'aws-cdk-lib';
+import { Duration, IResource, Resource, Token } from 'aws-cdk-lib';
 import * as cloudwatch from 'aws-cdk-lib/aws-cloudwatch';
 import * as kms from 'aws-cdk-lib/aws-kms';
 import { CfnSchedule } from 'aws-cdk-lib/aws-scheduler';
@@ -324,6 +324,9 @@ export class Schedule extends Resource implements ISchedule {
     const flexibleTimeWindow = props.timeWindow ?? TimeWindow.off();
 
     this.validateTimeFrame(props.start, props.end);
+    if (props.scheduleName && !Token.isUnresolved(props.scheduleName) && props.scheduleName.length > 64) {
+      throw new Error(`scheduleName cannot be longer than 64 characters, got: ${props.scheduleName.length}`);
+    }
 
     const resource = new CfnSchedule(this, 'Resource', {
       name: this.physicalName,

packages/@aws-cdk/aws-scheduler-alpha/test/schedule.test.ts

@@ -215,6 +215,17 @@ describe('Schedule', () => {
       }).toThrow('The provided duration must be between 1 minute and 1440 minutes, got 0');
     });
 
+    test('throw error when scheduleName exceeds 64 characters', () => {
+      const name = 'an-extremely-unnecessarily-long-name-exceeding-64-characters-in-length';
+      expect(() => {
+        new Schedule(stack, 'TestSchedule', {
+          schedule: expr,
+          target: new SomeLambdaTarget(func, role),
+          scheduleName: name,
+        });
+      }).toThrow(`scheduleName cannot be longer than 64 characters, got: ${name.length}`);
+    });
+
     test('schedule with description', () => {
       // WHEN
       new Schedule(stack, 'TestSchedule', {