Episode grid: move names out of the button into the tooltip

The visible names made the grid uneven (long titles wrapped to 2-3
lines). Buttons now show only the E-number; the full name lives in
the title attribute (hover tooltip: 'E1 — Ryomen Sukuna'). Dropped
the now-unused .ep-name CSS.

static/style.css

@@ -164,8 +164,6 @@ button.tiny.on { border-color: var(--acc); color: var(--acc); }
 
 .eps { display: grid; grid-template-columns: repeat(auto-fill, minmax(64px, 1fr)); gap: 0.4rem; }
 .ep { position: relative; font-size: 0.9rem; }
-.ep-name { display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical;
-  overflow: hidden; font-size: .68rem; color: var(--muted); margin-top: .2rem; line-height: 1.2; }
 .ep.filler { opacity: 0.55; }
 .ep.done { opacity: 0.5; }
 .ep.nextup { border-color: #4b5568; background: #1f2130; }