0.5.6 — Never drop fast Pencil strokes

Fix

Fast handwriting no longer skips strokes.

• Pencil uses a dedicated input path (not shared with palm/scroll logic)
• Missed tip-down starts on the first contact move
• Mid-stroke buttons=0 flicker no longer drops the stroke
• Lost active stroke re-opens ink instead of erasing
• Pen-up always commits if the engine still has a stroke

Reload Obsidian after update.