Bug: Whitespace normalization mismatch in Ralph Wiggum stop hook causes completion promise comparison to fail

Description

In plugins/ralph-wiggum/hooks/stop-hook.sh (lines 119, 123), the completion promise text extracted from output is whitespace-normalized via s/\s+/ /g, but the stored COMPLETION_PROMISE value is not normalized. This causes the comparison to fail when the user's promise contains multiple consecutive spaces.

Steps to Reproduce

1. Set a completion promise with multiple spaces: --completion-promise 'TASK DONE'
2. The promise is stored as-is: "TASK DONE" (4 spaces)
3. When extracted from output, whitespace is normalized to single spaces: "TASK DONE"
4. The comparison fails: "TASK DONE" != "TASK DONE"

Expected Behavior

The completion promise should be detected regardless of whitespace differences between the stored promise and the output text.

Suggested Fix

Normalize whitespace on the stored COMPLETION_PROMISE as well before comparison, or normalize both sides at comparison time.