fix: honor clicked blocks for debug stick interactions

[twme-ai]

Root cause

PlayerInteractEvent already identifies the exact clicked block, including its cursor hit position. Classic and Copy mode discarded that block and performed a second eye raycast with getTargetBlockExact(5). For short collision shapes such as candles, the second raycast could resolve the full block behind the candle. Sneaking changes the eye origin enough to hide the bug in some positions.

Fix

• carry the event's clicked block through Classic and Copy left/right-click handling
• fall back to an eye raycast only for air-click events
• consume the off-hand follow-up after a handled Debug Stick click so vanilla empty-hand candle interaction cannot undo the change
• remove the obsolete candle limitation from the README
• add an in-game candle regression that verifies both sneaking and non-sneaking interaction, including an off-hand follow-up packet

Verification

• mvn -B clean package (11 tests passed)
• Paper 1.19.4 E2E on Java 17
• Paper 1.20.6 E2E
• Paper 1.21.1 E2E
• Spigot 1.19.4 E2E on Java 17
• Folia 1.20.6 E2E
• existing locale, Freeze targeting, VirtualEntities removal, and barrier restoration assertions continue to pass
• Node syntax, Markdown lint, and git diff --check