feat(design): the field family, the dropdown trigger, native controls, the no-raw-input lint rule (E28 S3c)

- ui/Input, Textarea, InnerInput + fieldClass (A4): the >= 3:1 edge, a 2px accent
  focus edge, the danger edge for invalid, md/sm/xs/heading rungs, 1rem and 44 on touch
- ui/SelectTrigger (A5): SortControl, FilterSelect, the view switcher and the date
  filter on one trigger, a pill in a toolbar, r8 in a form
- ui/NativeControls (A6): Checkbox, CheckRow, Slider, ColorInput
- every raw input swept (~100 sites); inputCls retired; local/input-primitive
- useReturnFocus: an in-place editor hands the focus back to its trigger on
  Enter/Escape (the playlist and Plex title renames, the priority number);
  the Plex playlist rename gains Escape and an accessible name
- back to top: a round 48 FAB (owner decision); DESIGN.md A2 and the log

frontend/src/components/SearchBar.tsx

@@ -11,6 +11,7 @@ import { useSearchFocusKey } from "../lib/keymap";
 import { PaletteKeycap } from "./PaletteLauncher";
 import { Button } from "./ui/Button";
 import { IconButton } from "./ui/IconButton";
+import { InnerInput } from "./ui/Input";
 
 // The floating search pill in the top header. One component for every module that searches
 // (feed, Plex, channels, playlists): a glass rounded box with a search icon, the input, a
@@ -73,7 +74,8 @@ export default function SearchBar({
     <div className="pointer-events-auto relative flex-1 min-w-0 max-w-xl @min-[420px]/appmain:min-w-[15rem] @max-[640px]/appmain:order-last @max-[640px]/appmain:basis-full">
       <div className="h-11 pl-3 pr-2 rounded-2xl glass-menu flex items-center gap-2 focus-within:outline-2 focus-within:outline-accent/60 focus-within:outline-offset-2">
         {leading ?? <Search className="w-4 h-4 shrink-0 text-muted" />}
-        <input
+        <InnerInput
+          className="text-sm"
           {...inputProps}
           ref={inputRef}
           value={value}
@@ -90,7 +92,6 @@ export default function SearchBar({
             else if (e.key === "Escape") e.currentTarget.blur();
           }}
           placeholder={placeholder}
-          className="flex-1 min-w-0 bg-transparent outline-hidden text-sm placeholder:text-muted"
         />
         {value && (
           <IconButton onClick={() => onChange("")} label={t("header.clearSearch")}>