[M2-S8] Drone: hover, drop screws, dive #47

User story

As a player, I want a drone I can't easily beat with a chair, so that hiding under girders is a real choice and coming back later is worth it.

Acceptance criteria

• Hovers out of chair reach, drops screws or sparking batteries
• Dives when you're under it; red eye flash and tilt first
• 8 chair hits; hiding under girders breaks its line

Design and references

05 – Regular enemies. Cut 3rd if late (keep it as scenery).

Dependencies

Suggested owner: Vatsal (player and combat code).

Verification

Cross the low route under the drone without being hit.