[FR] CEG: boolean tag for trails to inherit projectile speed

See description. A boolean trait that makes CEG trails inherit velocity from their parent projectile.

No file, test, or entry point is identified in the issue. Start by locating the CEG trail implementation and the projectile velocity handling, then trace how trail traits are parsed and applied. Done means a boolean trait lets a CEG trail inherit velocity from its parent projectile, with coverage for the new behavior.

Written by the indexing model from the issue text.