Reduce frontend CPU and allocation overhead

What's Changed

• Reduce terminal cursor scanning overhead and track split paste-mode sequences without copying output buffers.
• Coalesce activity indicator transitions and timers, preserve unchanged session identities, and avoid redundant tab and sidebar updates.
• Reconcile Git panel rows in place, retain focus and unchanged diffs, and stop hidden or stale panels from rendering into the shared dock.
• Escape HTML without temporary DOM elements and keep keyed DOM cleanup linear for large lists.

Release integrity

Native archives have matching platform-specific SPDX SBOM assets plus GitHub build-provenance and SBOM attestations. Installers and the built-in updater additionally verify a signed manifest and all packaged-file hashes.

Verification guide · Security policy