Release v0.31.9

What's Changed

• fix(teleport): support default conversations [LET-11807] by @carenthomas in #4160
• fix(headless): send client tool allowlist with environment-routed turns by @letta-integration[bot] in #4171
• fix(headless): wait on environment turn liveness instead of a 10-minute deadline by @letta-integration[bot] in #4172
• fix(teleport): resume source after failed handoff [LET-11803] by @carenthomas in #4164
• feat(subagents): add computer parameter to the Agent tool by @letta-integration[bot] in #4170
• refactor(headless): drive the environment-turn wait from the runtime-status record by @letta-integration[bot] in #4174
• chore: bump version to 0.31.9 by @github-actions[bot] in #4165

Full Changelog: v0.31.8...v0.31.9