Signals in the needle's orange, and a larger DeadAir tile in the play bar (#268)

Each Signal's tile, icon or initials, is tinted --accent2 in place of
--accent: the orange point of the Signals folder's own icon, so the
folder and what is in it read as one. The player's DeadAir tile goes
from 22px to 26px in its 30px button.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/app.css

@@ -779,7 +779,7 @@ body.scan-this .fhead [data-a=scan] .i,body.scan-any .fhead [data-a=scanall] .i,
 /* Initials, tinted by a hash of the name so two "TS" in a row can be told apart. Mixed into the
    page ground, not --raise: that is also the selected row, and a selected tile vanished into it. */
 .art>.tile{width:100%;height:100%;display:block}
-#pdead .tile{width:22px;height:22px;border-radius:5px}
+#pdead .tile{width:26px;height:26px;border-radius:6px}
 .art.ini{background:color-mix(in srgb,var(--tint) 24%,var(--bg));color:var(--tint)}
 /* A folder: its first four shows' art, as iTunes built a playlist's from its albums. */
 .art.mosaic{grid-template:1fr 1fr/1fr 1fr;place-items:stretch}