feat: async knowledge support (#4023)

* feat: add async support for tools, add async tool tests

* chore: improve tool decorator typing

* fix: ensure _run backward compat

* chore: update docs

* chore: make docstrings a little more readable

* feat: add async execution support to agent executor

* chore: add tests

* feat: add aiosqlite dep; regenerate lockfile

* feat: add async ops to memory feat; create tests

* feat: async knowledge support; add tests

* chore: regenerate lockfile