Return 0 from sortFunc when values are equal

[Ujjwal-Gowda]

What this PR does:

sortFunc never returned 0. For equal values a > b is false, so it fell through to -1 in ASC and 1 in DESC, reporting both a < b and b < a for identical input.

Array.prototype.sort is only stable when the comparator returns 0 for equal elements, so equal entries were reordered instead of keeping their original order. With 12 entries where 11 share a name, the equal ones came out fully reversed. The result also varied with list length, because V8 switches sorting strategy for larger arrays.

This adds the a === b short-circuit, and adds web/src/utils/common.test.ts (the file did not exist before) covering ordering, equality, and the stability regression.

Why we need it:

This function sorts the piped and application lists in the four application forms and in the encrypt secret drawer, where duplicate names are normal. sortDateFunc delegates to sortFunc and had the same problem for equal timestamps.

The visible effect is that the dropdown order for same-named entries is unstable: it changes depending on how many items are in the list, so a user picking "the second api piped" is not picking a consistent thing.

Which issue(s) this PR fixes:

None — found while reading the application form code. Happy to open an issue first if that is preferred.

Does this PR introduce a user-facing change?:

• How are users affected by this change: Piped and application dropdowns keep same-named entries in their original order instead of reversing them.
• Is this breaking change: No.
• How to migrate (if breaking change): N/A

[github-actions]

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