[davidprokopec]

Summary

• Replace the unstyled Unicode/text Schedules action with OpenCode's native IconButton and Tooltip.
• Use the supported checklist icon for both toolbar and launcher, rather than the refresh-like rotate arrow.
• Set the native large size to match adjacent 28px panel-toolbar controls.
• Preserve the existing slot session target and panel-opening behavior; release opencode-schedule 0.5.1.

Verification

• Typecheck, lint, 155 tests (480 assertions), GUI build and diff checks pass.
• Actual isolated Desktop 2.2.5 confirms native control appearance, tooltip, checklist glyph, panel opening and repeat-click/no duplicate behavior.
• Measured native neighbours are 28px; size=large was experimentally verified to match, including hover/focus/session behavior. Final source combines that prop with the verified checklist control.
• Main checkout and its unrelated experimental branch/files were not changed.