disable font scaling on fixed-height chat invite cards

thread a hasFixedHeight flag through ChatInvite.Root and its context so
the card, join button, and profile badges disable font scaling when they
live in a fixed-height container, preventing text from overflowing.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/components/Typography.tsx

@@ -23,6 +23,7 @@ export function Text({
   title,
   dataSet,
   numberOfLines,
+  allowFontScaling = true,
   ...rest
 }: TextProps) {
   const {fonts, flags} = useAlf()
@@ -36,7 +37,7 @@ export function Text({
       style,
     ],
     {
-      fontScale: fonts.scaleMultiplier,
+      fontScale: allowFontScaling ? fonts.scaleMultiplier : 1,
       fontFamily: fonts.family,
       flags,
     },
@@ -57,6 +58,7 @@ export function Text({
     numberOfLines,
     style: s,
     dataSet: Object.assign({tooltip: title}, dataSet || {}),
+    allowFontScaling,
     ...rest,
   }