Plan mode auto-clear on accept not working (v2.1.81)

Description

v2.1.81 changelog states context auto-clears on plan accept. In practice, multiple ExitPlanMode cycles in a single session did not clear context. Session accumulated to 40%+ context utilization across 6+ plan mode entry/exit cycles.

Steps to Reproduce

1. Enter plan mode (EnterPlanMode)
2. Do substantial planning work (file reads, agent dispatches, plan file edits)
3. Exit plan mode (ExitPlanMode) - plan is approved
4. Do execution work
5. Re-enter plan mode for refinements
6. Exit again
7. Repeat 4-6 times

Expected

Context should auto-clear on each plan accept per changelog: "Changed plan mode to hide the 'clear context' option by default"

Actual

Context accumulated across all cycles. No automatic clearing occurred. Session hit 40%+ context with compaction warning.

Environment

• Claude Code version: 2.1.81
• Platform: Windows 11 (10.0.26200)
• Surface: Antigravity (Google VS Code fork)
• Model: Claude Opus 4.6 (1M context)

Workaround

Added showClearContextOnPlanAccept: true to settings to restore the manual clear option.