FEATURE REQUEST : flush out 2 most common needs for this architecture

1. ADD code and workflows for steps to prepare web app .
- build process and ENVs and all that
- about line 150 in README.md it states "Static objects uploaded to S3 are objects developed and built through Vue.js"
- line 58 - I used Vue.js for this project, but you can see how you can static web host a reactive front end similar to this.
all the API calls to show how the web app works are all in the dist folder even if they are in vue.js it would still be great to show
as example

2. ADD more detail with example for line 66 about lambda... most apps like this have a payment stripejs type of need so the need for working with lambda extra modules is almost always there.
`However, in the case of aws-lambda-nodejs provided by the CDK, you can bundle only with the module configuration required for nodejs lambda and proceed with deployment easily.`
this seems to be very common... so help a user out

BONUS: give instructions as OPTIONAL for the cognito constructs that are all commented out and leave commented out but have optional.
EXTRA BONUS: make it easy, aka provide steps commands, to update pass words for security since security it TOP priority for all in AWS Secrets Manager like in Step 8 line 174

Start with README.md around lines 58, 66, 150, and 174, then inspect the dist folder and the commented Cognito constructs mentioned in the issue. Document the web-app build and environment workflow, Lambda extra-module and payment-related usage, optional Cognito steps, and Secrets Manager password updates. Done means these workflows have concrete commands or examples that match the project.

Written by the indexing model from the issue text.