Echo Protocol

## Echo Protocol 0.5.0-beta.2 — Hotfix 1

This build contains a major cross-version stability and visual regression fix for Echo Protocol.

### Fixed

- Fixed Echoes sometimes using the default Steve skin instead of the target player's real skin.
- Fixed player skin data not being correctly propagated into the modern render state on newer Minecraft versions.
- Fixed fallback skins potentially remaining cached instead of updating to the real player skin.
- Fixed Echoes appearing fully opaque instead of translucent on Minecraft 1.21.9–1.21.11.
- Restored the intended ghost-like transparency, alpha and fade behavior.
- Fixed Echo movement being able to pass through solid blocks in some situations.
- Replaced unsafe movement behavior with collision-aware movement and swept-path validation.
- Memory Echoes now safely stop and fade out when an old recorded route has become blocked by newly placed blocks.
- Fixed The Original advancement being granted before The Original had actually manifested to the player.
- Advancement progression now waits for the corresponding gameplay event to successfully occur.
- Improved cleanup for failed or blocked Echo events.
- Improved player skin caching and validation across supported Minecraft versions.
- Fixed Minecraft 1.21.1 version metadata being too broad.

### Verification

Every supported Minecraft version from 1.21.1 through 1.21.11 was re-tested using dedicated Prism Launcher instances.

Final production JARs were tested for:

- Minecraft client startup
- Fabric dedicated server startup
- Custom player skins
- Echo transparency and fading
- Collision and wall handling
- Memory Echo playback
- The Original
- Event manifestation
- Advancements
- Gameplay behavior
- Persistence
- Multiplayer privacy on representative versions
- Client/server logs

52 automated tests also pass on the final builds.

### Important

This is a bug-fix release only.

There are no new gameplay features and the mod version remains 0.5.0-beta.2.

It is strongly recommended to replace older 0.5.0-beta.2 builds with this hotfix.