Refactor (packages/web/src/components/share/part.tsx): Function with high complexity: flattenToolArgs

[mmirzata]

Issue for this PR

Closes #62

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Qlty flagged flattenToolArgs in part.tsx for high complexity (count = 21). The array
branch repeated the same object-vs-leaf check the function already did at the top, adding
duplication and nesting.

I moved the function into a new part-utils.ts and exported it so it can be tested, and
rewrote it so objects and arrays share one path (arrays just format the key as [i]
instead of .key). Output is unchanged, so same [path, value] pairs.

I used Claude to help with the refactor and the tests, following the instruction alone was not enough.

How did you verify your code works?

Added part-utils.test.ts with 5 tests covering nested objects/arrays, primitives and
null, non-object input, empty inputs, and array bracket paths. All 5 pass with 100%
coverage on part-utils.ts, and qlty smells no longer reports the smell.

Screenshots / recordings

Before: Qlty smell (count = 21):

After: no smell on part-utils.ts:

Tests passing, 100% coverage:

Lint: filtering bun lint to my changed files returns nothing, confirming part-utils.ts and part.tsx have no lint errors (the repo's only lint errors are pre-existing, in unrelated files I didn't modify).

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR