The Broken Script Bedrock 2.0.7 — mostly 1:1 parity pass

Canonical reference: Java/source archive supplied with this build.

Implemented in this pass:
- Repaired null entity spawn ID (nulll).
- Repaired Nothing Is Watching chase entity ID.
- Repaired StareAtPlayerEvent to use the existing Bedrock stare system instead of spawning a nonexistent entity.
- Repaired the no-texture entity's item reference from serial_designation_n to the Java item n.
- Added Bedrock item registrations for Java-registered items that were absent from the BP.
- Added RP icon aliases for those restored items.
- Added the four Java fire-based chainmail crafting recipes.
- Updated BP/RP pack/module versions to 2.0.7.
- Removed nonexistent entity IDs from the owner spawn list and expanded it to include registered parity entities.
- Added a Bedrock-native Hand Cannon implementation with the Java damage/impulse modes; sneaking toggles mode because Bedrock does not expose the Java client screen API.
- Added display names for the newly registered items.

Known unavoidable/remaining differences:
- Java client crashes/window manipulation, direct filesystem writes, and Java-only renderer/camera hooks cannot be reproduced exactly with Bedrock Script API.
- Some Java block entities (notably the portal controller/extender system) still require Bedrock-native reimplementation rather than a direct code translation.
- Some Java item data components/menu behavior (notably LibraryBookItem's custom menu and per-stack data component) are approximated or remain content-only.
- Some Java block IDs are intentionally translated to vanilla Bedrock blocks by the existing dimension conversion layer.
