Complete dual-platform Homebrew packaging and isolate CLI upgrade channels

[Sailfishc]

Problem and behavior

Homebrew release validation previously used a temporary macOS-only formula, while CLI upgrades hardcoded an unrelated tap and queried the stable GitHub channel even for preview installs. Add a dual-platform formula generator for macOS arm64 and Linux x86_64, an explicit keg-only beta formula, and receipt-based routing through the Homebrew instance that owns the installation. Unknown receipts and channel changes fail safely. Homebrew upgrades still require stopped services and never stop tasks automatically.

Add publication-triggered tap synchronization with verified public archives and channel-specific updates. It retains read-only workflow permissions and fails explicitly when existing cross-repository authorization is absent; maintainers can use the same script with existing tap write access. Prepare CLI 0.1.7-beta.2 without changing the GUI version or stable update feeds.

The public tap is not available yet: the organization rejected the current maintainer's repository-creation request. Public first-install acceptance remains blocked until an authorized organization owner creates areal-project/homebrew-tap and grants existing maintainer write access. No credentials or security settings were created or expanded.

Validation

• 12 release/archive/checksum/installer/formula regression tests passed.
• Chinese/English documentation links and pairing passed (183 files).
• Rust formatting and 4 focused upgrade tests passed; 8 real CLI upgrade smoke tests passed.
• Local native macOS acceptance verified stable 0.1.5 to 0.1.6, beta.1 to beta.2, beta isolation, actual receipt tap routing through the owning brew, Runtime read/write smoke, and real active-task preservation/refusal. A local post-upgrade brew test child had a signal-style exit; bundle bytes and signatures matched and its exact read-only rerun passed. Hosted native CI remains required before merge.
• Linux bundles retain the Ubuntu 22.04 / glibc 2.35 build and installer baseline. A separate Ubuntu 24.04 / glibc 2.39 job validates the identical archive through native Linuxbrew, respecting Homebrew host requirements without ignoring dependencies.
• Release CI now exercises isolated native Homebrew prefixes on macOS and Linux: published older stable/beta archives, upgrade, keg-only coexistence, actual-source checks, complete Runtime smoke and an active-task refusal without stopping the service. Existing standalone installer and Linux native-tool checks remain enabled.
• Public tap acceptance remains blocked as described above. Temporary tap tests will not be reported as public-channel availability.

Documentation

Update both installation guides and release guides with separate first-install/upgrade commands, stable/beta isolation, Linux prerequisites and explicit synchronization failure recovery. Personal release skills are updated locally and are not included in this repository.

Generalization evidence

This changes distribution and installation-source routing, not agent policies, prompts, budgets or task behavior. Regression invariants apply to actual receipt ownership, channel separation, integrity and backend preservation; no agent-quality improvement is claimed.