[optimize] speed up diffKeys() with native Set intersection/difference semantics

[Copilot]

diffKeys() previously built status maps via two array passes and per-item mutation. This update moves key comparison to set algebra, reducing duplicate work and aligning behavior with modern Set APIs.

• Set-based key diff core

  • Reworked diffKeys() to compare oldList/newList via Set operations:
    • old \ new → DiffStatus.Old
    • old ∩ new → DiffStatus.Same
    • new \ old → DiffStatus.New
  • Keeps output shape unchanged (map + grouped entries).

• Native latest-API usage

  • Uses Set.prototype.difference() and Set.prototype.intersection() directly (no built-in compatibility fallback).

• Deterministic duplicate handling

  • Added focused coverage for duplicate keys to ensure duplicates are de-duplicated by set semantics and do not skew status classification.

const oldSet = new Set(oldList);
const newSet = new Set(newList);

for (const item of getSetDifference(oldSet, newSet)) map[item] = DiffStatus.Old;
for (const item of getSetIntersection(oldSet, newSet)) map[item] = DiffStatus.Same;
for (const item of getSetDifference(newSet, oldSet)) map[item] = DiffStatus.New;

Human changes

1. [refactor] simplify methods with Base64 & Hex utility API of Uint8Array (53e4972)
2. [migrate] upgrade to TypeScript 6, PNPM 11, Lint-Staged 17 & other latest Upstream packages/actions
3. [optimize] simplify Copilot codes

[TechQuery]

@copilot

[Copilot]

@copilot

已按评审意见改为直接使用最新 Set API，移除了兼容性 fallback。提交：5017736

[Copilot]

Pull request overview

This PR refactors diffKeys() to use set-based semantics for classifying keys as Old/Same/New, and adds a regression test to ensure duplicate keys don’t affect the classification results.

Changes:

• Reworked diffKeys() to derive Old/Same/New sets from oldList and newList.
• Added a unit test ensuring duplicate keys are ignored during comparison.
• Bumped package version to 4.7.1.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
source/data.ts	Refactors diffKeys() to compute key statuses using Set-based logic.
test/data.spec.ts	Adds coverage to ensure duplicates do not skew diffKeys() results.
package.json	Bumps the published package version.

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