DP17: use folds Icons + named brand-color consts in UrlPreviewCard

Replace literal-glyph UI icons in the URL preview cards with folds
Icon/Icons components, and hoist hardcoded provider brand hex values
into a single named BRAND_COLORS map.

Glyph -> folds icon:
- TikTok/Spotify musical note (♫) -> Icons.VolumeHigh
- Portrait play button (▶)        -> Icons.Play
- Reddit comment count (💬)       -> Icons.Message
- Steam gear (⚙)                  -> Icons.Setting
All use size="Inherit" so they keep the surrounding font-size/color.

Brand hex now referenced via BRAND_COLORS (tiktok, spotify, steam,
twitch, reddit, discord, npm, stackOverflow) instead of scattered
literals; colors are byte-for-byte identical and remain fixed brand
identities (not converted to TDS theme vars).

The game controller glyph (🎮) is left as-is: folds has no game/
controller icon and no close semantic match.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/components/url-preview/UrlPreviewCard.tsx

@@ -33,6 +33,22 @@ import {
 
 const linkStyles = { color: color.Success.Main };
 
+// ---------------------------------------------------------------------------
+// Provider brand identity colors.
+// These are official brand-palette values (logos, badges), NOT theme colors,
+// so they intentionally stay as fixed hex and must not become --lt-* TDS vars.
+// ---------------------------------------------------------------------------
+const BRAND_COLORS = {
+  tiktok: '#EE1D52',
+  spotify: '#1db954',
+  steam: '#c7d5e0',
+  twitch: '#9146ff',
+  reddit: '#ff4500',
+  discord: '#5865f2',
+  npm: '#cb3837',
+  stackOverflow: '#f48024',
+} as const;
+
 // ---------------------------------------------------------------------------
 // Helpers — URL parsing & variant detection
 // ---------------------------------------------------------------------------
@@ -474,7 +490,11 @@ function TikTokCard({
       <div className={previewCss.ShortsHeader}>
         {/* TikTok badge with musical note icon */}
         <span className={`${previewCss.SiteBadge} ${previewCss.BadgeTikTok}`}>
-          <span style={{ color: '#EE1D52', marginRight: '2px' }}>♫</span>
+          <Icon
+            style={{ color: BRAND_COLORS.tiktok, marginRight: '2px' }}
+            size="Inherit"
+            src={Icons.VolumeHigh}
+          />
           TikTok
         </span>
         {username && (
@@ -512,12 +532,14 @@ function TikTokCard({
               loading="lazy"
             />
             <div className={previewCss.PortraitPlayOverlay}>
-              <div className={previewCss.PortraitPlayButton}>▶</div>
+              <div className={previewCss.PortraitPlayButton}>
+                <Icon size="Inherit" src={Icons.Play} />
+              </div>
             </div>
           </a>
         ) : (
           <div className={previewCss.PortraitPlaceholder}>
-            <span style={{ color: '#EE1D52' }}>♫</span>
+            <Icon style={{ color: BRAND_COLORS.tiktok }} size="Inherit" src={Icons.VolumeHigh} />
           </div>
         )}
         <Box grow="Yes" direction="Column" gap="100">
@@ -828,7 +850,7 @@ function TwitchCard({
             width={28}
             height={28}
             viewBox="0 0 24 24"
-            fill="#9146ff"
+            fill={BRAND_COLORS.twitch}
             aria-hidden="true"
             role="img"
           >
@@ -921,11 +943,11 @@ function RedditCard({
             width={28}
             height={28}
             viewBox="0 0 24 24"
-            fill="#ff4500"
+            fill={BRAND_COLORS.reddit}
             aria-hidden="true"
             role="img"
           >
-            <circle cx="12" cy="12" r="12" fill="#ff4500" />
+            <circle cx="12" cy="12" r="12" fill={BRAND_COLORS.reddit} />
             <path
               fill="#ffffff"
               d="M20 12a2 2 0 0 0-2-2 2 2 0 0 0-1.36.54C15.28 9.8 13.72 9.4 12 9.39l.7-3.26 2.23.47a1.4 1.4 0 1 0 .15-.69l-2.5-.52a.25.25 0 0 0-.29.19l-.78 3.65c-1.74.06-3.3.46-4.63 1.17A2 2 0 0 0 4 12a2 2 0 0 0 1.07 1.76 3.5 3.5 0 0 0 0 .49C5.07 16.69 8.27 19 12.07 19s6.97-2.31 6.97-4.75a3.5 3.5 0 0 0 0-.47A2 2 0 0 0 20 12zm-13 2a1 1 0 1 1 2 0 1 1 0 0 1-2 0zm5.59 2.71c-.72.72-2.1.77-2.53.77s-1.82-.05-2.53-.77a.25.25 0 0 1 .35-.35c.46.46 1.48.62 2.18.62s1.72-.16 2.18-.62a.25.25 0 0 1 .35.35zm-.15-1.71a1 1 0 1 1 2 0 1 1 0 0 1-2 0z"
@@ -1005,7 +1027,11 @@ function RedditCard({
           {/* Stats row */}
           <div className={previewCss.RedditMeta}>
             {upvotes && <span className={previewCss.RedditUpvote}>▲ {upvotes}</span>}
-            {comments && <span>💬 {comments}</span>}
+            {comments && (
+              <span>
+                <Icon size="Inherit" src={Icons.Message} /> {comments}
+              </span>
+            )}
           </div>
         </Box>
 
@@ -1473,7 +1499,11 @@ function SpotifyCard({ url, prev }: { url: string; prev: IPreviewUrlResponse })
           justifyContent="Center"
           className={previewCss.IconWrapper}
         >
-          <span style={{ fontSize: '2rem', color: '#1db954' }}>♫</span>
+          <Icon
+            style={{ fontSize: '2rem', color: BRAND_COLORS.spotify }}
+            size="Inherit"
+            src={Icons.VolumeHigh}
+          />
         </Box>
       )}
       <UrlPreviewContent>
@@ -1533,7 +1563,11 @@ function SteamCard({ url, prev }: { url: string; prev: IPreviewUrlResponse }) {
           justifyContent="Center"
           className={previewCss.IconWrapper}
         >
-          <span style={{ fontSize: '1.5rem', color: '#c7d5e0' }}>⚙</span>
+          <Icon
+            style={{ fontSize: '1.5rem', color: BRAND_COLORS.steam }}
+            size="Inherit"
+            src={Icons.Setting}
+          />
         </Box>
       )}
       <UrlPreviewContent>
@@ -1640,7 +1674,7 @@ function DiscordCard({ url, prev }: { url: string; prev: IPreviewUrlResponse })
             width={28}
             height={28}
             viewBox="0 0 24 24"
-            fill="#5865f2"
+            fill={BRAND_COLORS.discord}
             aria-hidden="true"
             role="img"
           >
@@ -1693,13 +1727,13 @@ function NpmCard({ url, prev }: { url: string; prev: IPreviewUrlResponse }) {
       >
         {/* npm logo — simple square mark */}
         <svg width={32} height={32} viewBox="0 0 18 7" fill="none" aria-hidden="true" role="img">
-          <rect width="18" height="7" fill="#cb3837" />
+          <rect width="18" height="7" fill={BRAND_COLORS.npm} />
           <rect x="1" y="1" width="4" height="5" fill="white" />
-          <rect x="2" y="1" width="1" height="4" fill="#cb3837" />
+          <rect x="2" y="1" width="1" height="4" fill={BRAND_COLORS.npm} />
           <rect x="6" y="1" width="4" height="5" fill="white" />
-          <rect x="7" y="1" width="1" height="3" fill="#cb3837" />
+          <rect x="7" y="1" width="1" height="3" fill={BRAND_COLORS.npm} />
           <rect x="11" y="1" width="4" height="4" fill="white" />
-          <rect x="12" y="1" width="1" height="3" fill="#cb3837" />
+          <rect x="12" y="1" width="1" height="3" fill={BRAND_COLORS.npm} />
         </svg>
       </Box>
       <UrlPreviewContent>
@@ -1747,7 +1781,7 @@ function StackOverflowCard({ url, prev }: { url: string; prev: IPreviewUrlRespon
           width={28}
           height={28}
           viewBox="0 0 24 24"
-          fill="#f48024"
+          fill={BRAND_COLORS.stackOverflow}
           aria-hidden="true"
           role="img"
         >