docs(angular): update testing ng-add

[soundproofboot]

Issue number: resolves ionic-team/ionic-docs#2091

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What is the current behavior?

Documentation to test ng add schematic for @ionic/angular is outdated.

What is the new behavior?

More steps added to install and build libraries, change using npx schematics for ng add.

Does this introduce a breaking change?

• Yes
• No

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Name	Status	Preview	Comments	Updated (UTC)
ionic-framework	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jun 30, 2025 8:09pm

[brandyscarney]

I ran into some errors while testing out these steps and found that we needed to add a fix to support the latest Angular build system. I created a PR here with updated steps & a fix. I will add you as a co-author on that PR, but could you let me know if you see any issues? Thank you! 🙂

[soundproofboot]

I ran into some errors while testing out these steps and found that we needed to add a fix to support the latest Angular build system. I created a PR here with updated steps & a fix. I will add you as a co-author on that PR, but could you let me know if you see any issues? Thank you! 🙂

@brandyscarney Yes, I have not gotten the schematic to work any which way with Angular 20 but assumed that was a separate issue and wasn't sure how to approach that. I will test out the steps in that PR tomorrow and comment back here with the results.

[soundproofboot]

@brandyscarney I verified I was getting that same error with Angular 20.0.5 and then followed the new steps on the fix branch. Everything was easy to follow and installed with no issues. I also tried with 19 and works the same. Thank you, I had tried to debug the schematic but did not get very far.