v0.21.0

What's Changed

• feat(agent): meta-cognitive reminders by @cniska in #239
• feat(lifecycle): add signal tools by @cniska in #246
• feat(memory): distill observations via tool call by @cniska in #247
• feat(provider): support prompt caching by @cniska in #248
• refactor: break circular imports and fix tui layer boundary by @cniska in #250
• refactor(trace): add typed event catalog by @cniska in #261
• refactor(lifecycle): extract generate policy by @cniska in #260
• refactor(tools): deepen runTool pipeline by @cniska in #259
• feat(tools): add bounded file-read windows by @cniska in #263
• chore(deps): refresh deps and migrate ai-sdk to v4 by @cniska in #265
• fix(agent): preserve answers on signal turns by @cniska in #266
• fix: prompt ordering, reasoning migration, usage telemetry by @cniska in #271
• fix(tui): always install the client log sink by @cniska in #272
• fix(chat): stop dropping the final answer by @cniska in #273

Full Changelog: v0.20.0...v0.21.0