Configurable Idle-Detection Threshold

Use Case: Prompt-first development (writing prompts, followed by longer reading and thinking periods while waiting for or analyzing AI results).

Problem: Thinking/reading often takes longer than 5 minutes, triggering an automatic pause between time entries when you are actually still working.

Proposed Solution: Allow users to adjust the idle detection threshold (e.g., set it to 10, 15, or custom minutes) rather than keeping it locked at 5 minutes.