Expanded Ultrathink Triggers

What changed: Ultrathink mode now recognizes natural language variations

Trigger phrases:

• "ultrathink" (original)
• "think ultra hard" (new)
• "think ultrahard" (new)

Details:

• More discoverable and intuitive for users
• Backward compatible with original trigger
• Evidence: DU1() at line 361856 (replaces dw1() at line 366346 in v1.0.120)