feat(fonts): use Space Grotesk for all headings and OG cards

Point --font--title to Space Grotesk (--font-logo) for h1-h5 headings
and update both OG card components to use Space Grotesk for titles,
creating consistent brand typography across site and social previews.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: MaxDaten

src/lib/scss/typography.css

@@ -59,7 +59,7 @@ h2,
 h3,
 h4,
 h5 {
-    font-family: var(--font--default);
+    font-family: var(--font--title);
     line-height: var(--text-heading-leading);
 }
 

src/lib/scss/variables.css

@@ -1,7 +1,7 @@
 :root {
     /* Fonts */
     --font--default: 'Inter', sans-serif;
-    --font--title: var(--font--default);
+    --font--title: var(--font-logo);
     --font-logo: 'Space Grotesk Variable', Arial, Helvetica, sans-serif;
     --font--mono: 'JetBrains Mono', monospace;
 

src/routes/[slug]/og.jpg/OgCard.svelte

@@ -143,12 +143,12 @@
 
     h1 {
         display: flex;
-        font-family: 'Inter Variable', 'Inter', sans-serif;
+        font-family: 'Space Grotesk', sans-serif;
         font-size: 44px;
         line-height: 1.15;
         color: white;
         margin: 0 0 12px 0;
-        font-weight: 800;
+        font-weight: 700;
         text-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
     }
 

src/routes/og.jpg/ProfileOgCard.svelte

@@ -128,7 +128,7 @@
     h1 {
         display: flex;
         flex-direction: column;
-        font-family: 'Inter Variable', 'Inter', sans-serif;
+        font-family: 'Space Grotesk', sans-serif;
         font-size: 64px;
         line-height: 1.1;
         color: white;