fix(aws-cdk): init templates use outdate node types

[trivikr]

Fixes #935

The app needs to be on node@24, as we would like customers to run their applications on latest LTS of Node.js.
The lib needs to be node@20, as we would like customers to support minimum number of supported Node.js version.

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.05%. Comparing base (30ee4c9) to head (274d6bf).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #941      +/-   ##
==========================================
+ Coverage   83.83%   84.05%   +0.22%     
==========================================
  Files          71       71              
  Lines       10437    10437              
  Branches     1335     1334       -1     
==========================================
+ Hits         8750     8773      +23     
+ Misses       1648     1626      -22     
+ Partials       39       38       -1     

Flag	Coverage Δ
suite.unit	84.05% <ø> (+0.22%)	⬆️

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[mrgrain]

Thanks! See comments.