fix(themes): dim the summer rasi search placeholder + latte/backdrop findings (item 28c)

Both summer whole-swap rasi rendered prompt and placeholder in the
same bg0 on the green inputbar, reading as one run-on phrase — the
placeholder is now bg0 at 60% alpha, matching the generated theme's
hierarchy.

Recorded with it: the catppuccin-latte 1080p capture shows the
generated menu fully coherent on light themes (the audit's "dark
terminal on latte" was a stale preview), and a dedicated VM probe
confirms misc:background_color is applied (hyprctl getoption =
0xFFEFF1F5) — the dark backdrop in captures is awww's empty-state
layer over it, a wallpaper-less-VM artifact, not a defect.

Verified: rasi edits grep-verified (visual rides the next summer
capture / hardware); latte capture + probe reviewed. Item 28 is now
gated on the icon-weight [human] call and the queued hardware
eyeballs.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

themes/summer-day/rofi.rasi

@@ -68,7 +68,8 @@ entry {
     text-color: inherit;
     cursor: text;
     placeholder: "Type to search...";
-    placeholder-color: @bg0;
+    /* dimmed vs the prompt (item 28c) — bg0 at ~60% over the green */
+    placeholder-color: #fdf6e399;
 }
 
 listview {