v0.84.0

What's Changed

• feat(shell): add opt-in sandboxing with cross-platform workspace paths by @Wh1isper in #267
• feat(agent-sdk): add self fork delegate by @Wh1isper in #268
• fix(yaacli): drop stale shell wakeups by @Wh1isper in #269
• fix(agent-sdk): guard self fork concurrency by @Wh1isper in #270
• feat(filesystem): add ripgrep-backed search by @Wh1isper in #271

Full Changelog: v0.83.0...v0.84.0