fix: docs links point to the generated case-preserved slugs

/docs/libraries 404s live — the Libraries doc generates at
/docs/Libraries (loader preserves filename stems). Both hand-written
hrefs updated; targets verified against production.

Author: ronaldtse

src/pages/docs/index.astro

@@ -41,7 +41,7 @@ transliterate("bgnpcgn-ukr-Cyrl-Latn-2019", "Антон")
         <div class="tile card">
           <h3>Python</h3>
           <pre><code>pip install secryst</code></pre>
-          <a href="/docs/libraries">All libraries →</a>
+          <a href="/docs/Libraries">All libraries →</a>
         </div>
         <div class="tile card">
           <h3>Neural models</h3>

src/pages/index.astro

@@ -47,7 +47,7 @@ for (const code of systemCodes) {
         <div class="hero-cta">
           <a class="btn btn-accent" href="/demo">Try live transliteration →</a>
           <a class="btn btn-ghost" href="/maps">Browse {totalSystems} systems</a>
-          <a class="btn btn-ghost" href="/docs/libraries">Use it in your code</a>
+          <a class="btn btn-ghost" href="/docs/Libraries">Use it in your code</a>
         </div>
         <dl class="hero-stats tnum">
           <div>