Update Sparkle and configure sandboxed macOS updates

[austin-smith]

What Changed

• Update Sparkle from 2.9.4 to 2.10.0 and raise the package minimum to 2.10.0.
• Enable Sparkle’s installer service and add its required communication entitlements to the direct-download macOS target, preserving the existing App Group.

Why

Pick up Sparkle’s macOS 27 compatibility and installer fixes. The sandboxed macOS app also needs the installer service and communication permissions to install updates. A separate entitlements file keeps those permissions out of the iOS and Mac App Store targets.

Related: #48.

Validation

• Xcode 27: signed macOS Debug build, iOS Debug build, Mac App Store Release build, and unsigned macOS Release archive passed.
• All 223 macOS tests passed; SwiftLint passed with two existing About-view warnings.
• Verified embedded Sparkle 2.10.0, installer service, Boolean configuration, and expanded entitlements in the signed macOS app; verified the App Store app excludes Sparkle.
• Generated a local test DMG/appcast and verified its signature with a disposable key, macOS 26 minimum, and disabled deltas.
• Production signing, installation, and relaunch remain to be validated before release.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-16T01:04:48.399300Z	e668b24	Draft marked ready

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