Require Swift 6.2 toolchain

[colemancda]

Summary

Raises the minimum Swift toolchain for this package to 6.2, matching GATT's existing requirement (PureSwift/GATT#42).

Changes

• Package.swift: swift-tools-version 6.0 → 6.2.
• CI (swift.yml):
  • Linux matrix: drop swift:6.0.3 and swift:6.1.2 containers (can no longer parse a 6.2 manifest); keep swift:6.2.3 and swift:6.3.2.
  • android-build-arm: bump the container and the finagolfin Android SDK from 6.1.3 to 6.2 (swift:6.2.0 container, matching the SDK's exact compiler version — .swiftmodule files require an exact match, per the existing comment in the workflow).
  • ARM, WASM, Windows, and Embedded workflows were already pinned to 6.3.2 and need no change.
• README: Swift badge 6.0 → 6.2.

Test plan

• swift build succeeds (tools-version 6.2 manifest parses, no source changes required)
• swift test passes (522/522)
• Verified the new Android SDK checksum via swift package compute-checksum

[github-code-quality]

Code Coverage Overview

Languages: Swift

Swift / code-coverage/llvm-cov

The overall coverage in commit 1fca408 in the feature/require-swif... branch remains at 88%, unchanged from commit 7cd6513 in the master branch.

---

_{Updated July 21, 2026 04:55 UTC}