The user-message hook exits with code 3 (USER_MESSAGE_ONLY), which Claude
Code interprets as a hook failure, displaying "SessionStart:startup hook
error" on every session start. The context hook already handles injecting
context into the conversation, making the user-message hook redundant.
Removing it eliminates the spurious error message and saves ~60 seconds
of potential timeout on systems where the worker is slow to respond.
Closes#905
Rod Boev
fececc4e51