ultraplan: 30-min timeout silently discards all generated output and wastes tokens

Problem

When running /ultraplan with a complex, multi-step analysis, the session is silently terminated after 30 minutes if the user hasn't approved the plan in the web UI.

The result:

• All work done by the agents (analysis, findings, generated files) is completely lost
• Tokens consumed by those agents are wasted — no output is persisted
• The user receives no warning that a timeout is approaching
• The user receives no warning that work will be discarded if not approved in time

Steps to Reproduce

1. Run /ultraplan <complex multi-step task> — e.g., a full codebase audit across many files
2. The web session starts and agents begin working
3. After 30 minutes, if the user hasn't clicked "Approve" in the browser, the session terminates
4. All agent output is gone — no files saved, no commits, no artifacts

Expected Behavior

• Warn the user before the session starts that there is a 30-minute approval window
• Warn again when ~5 minutes remain (e.g., a notification in the terminal)
• OR: persist intermediate output to disk/branch as agents complete work, so it's not lost on timeout
• OR: extend the timeout or make it configurable for long-running analyses

Actual Behavior

• No warning about timeout
• No intermediate persistence
• Tokens consumed, output lost
• User only finds out after the session is already dead

Impact

• Significant token waste on complex tasks
• User frustration and loss of trust in the feature
• Long analyses (>30 min) are effectively unusable with ultraplan

Environment

• Platform: Windows 11
• Shell: Claude Code CLI
• Task type: Multi-agent codebase audit (7 parallel agent groups)