chore: bump version to v5.2.6 and update README What's New

Covers merged PRs bfly123#87, bfly123#91, bfly123#92, bfly123#96, bfly123#97: Gemini CLI 0.29.0
dual-hash support, OpenCode async deadlock fix, mail setup v3
compat, lpend stale-registry fallback, and autostart routing.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Improve tmux Claude ask stability and bump v5.1.3

release: v5.1.1 - unified daemon and bug fixes

- Unified askd daemon for all providers
- Fixed install/uninstall bugs
- Fixed kill/termination issues

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

v5.0.4: OpenCode -r 恢复判定修复

v5.0.3: 全新的稳定守护进程设计

Fix tmux split tests

Release v5.0.1