refactor(cli): replace getters and setters with a public field

[rix0rrr]

The CliIoHost had a number of fields that had the following pattern:

class CliIoHost {
  private _someField: string;

  /** Get someField */
  public get someField() {
    return this._someField;
  }

  /** Set someField */
  public set someField(value: string) {
    this._someField = value;
  }
}

There is no additional code in the getters and setters other than directly forwarding every access to a private field, so the above is equivalent to the following:

class CliIoHost {
  public someField: string;
}

Since the above is simpler, this PR proposed to remove the getters and setters and just expose the field mutably.

If we ever want to run additional code in a setter in some of these fields, we can refactor back to a getter and setter pair without impacting source or binary compatibility (forwards compatibility was the argument in the olden C++ and Java days for pre-emptively wrapping fields in getters and setters, but doesn't apply in JS land).

(🤖 This PR was generated using AI)

---

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

[mrgrain]

thanks!

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 85.71429% with 5 lines in your changes missing coverage. Please review.

Project coverage is 84.95%. Comparing base (ac56f9b) to head (f52c851).

Files with missing lines	Patch %	Lines
packages/aws-cdk/lib/toolkit/cli-io-host.ts	85.71%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #215      +/-   ##
==========================================
- Coverage   85.23%   84.95%   -0.28%     
==========================================
  Files         208      208              
  Lines       35710    35657      -53     
  Branches     4654     4599      -55     
==========================================
- Hits        30437    30294     -143     
- Misses       5114     5212      +98     
+ Partials      159      151       -8     

Flag	Coverage Δ
suite.unit	84.95% <85.71%> (-0.28%)	⬇️

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