docs: bump theme to v0.3.0 for code block fix, clean up homepage header

Code blocks:
- Bumped @sentry/starlight-theme from ^0.2.0 to ^0.3.0 — v0.2.0 had
  --ve-code-bg: #111 which made code blocks darker than intended.
  v0.3.0 uses #141419, matching the theme playground reference.

Homepage header:
- Removed the 'Sentry CLI' text from the homepage header — now shows
  just the wordmark SVG logo like production does. The text next to
  the logo icon looked redundant.

Author: sentry-junior[bot]

docs/bun.lock

@@ -10,7 +10,7 @@
   "dependencies": {
     "@astrojs/starlight": "^0.39.2",
     "@sentry/astro": "^10.38.0",
-    "@sentry/starlight-theme": "^0.2.0",
+    "@sentry/starlight-theme": "^0.3.0",
     "astro": "^6.3.5",
     "sharp": "^0.33.5",
     "shiki": "^3.21.0"

docs/package.json

@@ -27,8 +27,7 @@ const base = baseUrl.endsWith("/") ? baseUrl : baseUrl + "/";
   <div class="header sentry-header header-homepage">
     <div class="title-wrapper sl-flex">
       <a href={base} class="site-title sl-flex">
-        <img src={`${base}glyph.svg`} alt="" class="homepage-logo" />
-        <span class="homepage-title">Sentry CLI</span>
+        <img src={`${base}wordmark-light.svg`} alt="Sentry CLI" class="homepage-logo" />
       </a>
     </div>
     <div class="sentry-header-actions sl-flex print:hidden">
@@ -65,13 +64,6 @@ const base = baseUrl.endsWith("/") ? baseUrl : baseUrl + "/";
     width: auto;
   }
 
-  .homepage-title {
-    font-family: var(--sl-font);
-    font-size: 1.25rem;
-    font-weight: 700;
-    color: var(--ve-text, #fafafa);
-  }
-
   .header-nav-link {
     color: #fff !important;
     text-decoration: none;