Improve platform validation normalization and type safety

[TheBinaryAVA]

Issue Description

Summary

The current platform validation works correctly for exact matches, but there are a few edge cases and improvements that could make it more robust and developer-friendly.

Current Issues

1. Case sensitivity

Platform validation currently fails for values like:

['GitHub']
['GITHUB']

because validation only accepts lowercase exact matches.

### 2. Whitespace handling

Inputs containing leading/trailing whitespace fail validation:

[' github ']
### 3. Duplicate validation behavior

Invalid duplicated values can produce multiple errors:

['abc', 'abc']

Current output:

Unknown platform
Duplicate platform

This may create noisy validation results.

###4. Missing platform type safety

PLATFORMS is currently inferred as string[], which misses:

autocomplete support
compile-time validation
stricter platform typing
Proposed Changes
Normalize platform input using:
trim()
toLowerCase()
Add typed platform constants using as const
Introduce a Platform type
Improve duplicate validation flow
Optionally skip duplicate checks for invalid entries

###Expected Benefits
Better UX for user input
More resilient validation
Stronger TypeScript support
Cleaner error reporting

- enhancement
- typescript
- validation
- good first issue



```bash
fix/platform-validation-normalization

[Xenon010101]

Hi @Harxhit, I can improve the platform validation with case-insensitive matching and whitespace handling. Please assign it to me under GSSoC 26.

[eshan-tiwari]

Hi @Harxhit ,

I’m a GSSoC’26 contributor and would love to work on this issue. I’ve gone through the problem statement and I’m confident I can solve it efficiently.

Could you please assign this issue to me?

Thank you!

[Harxhit]

@TheBinaryAVA I have assigned this issue to you please wait for issue to get assigned before pushing a PR. It is clear violation of our COC.

[TheBinaryAVA]

@Harxhit Got it, thanks for pointing that out. I understand the process now and will wait for assignment before working on or opening a PR going forward. Appreciate the clarification—won’t happen again. Could you please take a look at the PR when you get a chance for approval?