chore(main): release 0.16.0

[github-actions]

🤖 I have created a release beep boop

0.16.0 (2026-07-18)

Features

• built-in web search with auto-search, citation audit, and progressive trace (#312) (7972b31)
• ci: ship Thuki Nightly as side-by-side signed install (#336) (3810dd1)
• conversation-wide search evidence reuse (#330) (1fe32a4)
• cut ForceWeb search latency and harden answer quality (#324) (51d2c1f)
• history: auto-save chats with retention and free chats (#331) (057b089)
• move Diagnostics to Behavior tab with trace retention and folder actions (#325) (70d68ac)
• search language parity across retrieval and answers (#326) (9005d44)
• search resilience and citation a11y (#327) (e8e2fd7)
• search trust and lawfulness package (#323) (151adf6)
• settings: Changelog tab with full release history (#328) (fd909fe)

Bug Fixes

• ci: make engine-gate throughput report-only instead of a blocking floor (#321) (07f1ca8)
• disclose when a requested web search can't reach the web or finds nothing (#314) (2a4d749)
• models: gate browse installs to chat brains only (07e0b35)
• models: gate Browse installs to chat brains only (#337) (07e0b35)
• search: disclose when a requested web search is unreachable or finds nothing (2a4d749)
• surface the 80% memory headroom rule in the model-fit warning (#322) (a9d5bb4)
• wire Auto search learn URL to disclosure blog post (#335) (01a99e2)

---

This PR was generated with Release Please. See documentation.

[github-actions]

🤖 Created releases:

• v0.16.0

🌻