CobbleGacha Expanded Alpha 3.7.18

Gacha animation polish:
- Keeps the existing 3.7.17 portal / summon animation.
- Starburst rays are now true BACKGROUND effects:
  * rendered before the portal
  * begin outside the portal core
  * no lines travel all the way into the centre
  * main portal/Pokeball stays visually in front
- Removed centre-crossing ULTRA star/cross lines.
- Replaced the oversized/drifting gold square treatment with one compact gold
  frame locked to the exact Pokeball/portal centre.
- Added an animated RGB/rainbow pulse that travels around the cinematic border.
  A second weaker pulse runs opposite it for balance.
- ULTRA late shockwave/reveal rays also keep a hollow centre so they never draw
  through the result.
- Existing text suppression, centred portal, ULTRA timing and reveal effects remain.
- No gameplay/gacha probability logic changed.
