liveline: add Link component, OL, remove BackButton, dedent code blocks, spacing tweaks

- Add A (link) component with --ll-accent color, bright #58a6ff in dark mode
- Add OL (ordered list) component for numbered steps
- Remove BackButton from EditorialPage
- Use string-dedent for all CodeBlock strings, properly indented in source
- Getting started steps as OL with clickable Chrome Web Store link
- Star on GitHub link in intro paragraph
- Inline heading rule (flex + 1px line) replaces separate Divider
- Heading padding 24px top/bottom, article gap 32px
- Sidebar TOC item spacing increased to 5px
- Centered image captions

website/src/components/markdown.tsx

@@ -114,7 +114,7 @@ export function TableOfContents({
                 fontWeight: 475,
                 lineHeight: "15.6px",
                 letterSpacing: "-0.04px",
-                padding: "3px 0",
+                padding: "5px 0",
                 color: defaultColor,
                 fontFamily: "var(--ll-font-primary)",
                 transition: "color 0.15s ease",
@@ -249,6 +249,29 @@ export function Caption({ children }: { children: React.ReactNode }) {
   );
 }
 
+export function A({ href, children }: { href: string; children: React.ReactNode }) {
+  return (
+    <a
+      href={href}
+      target="_blank"
+      rel="noopener noreferrer"
+      style={{
+        color: "var(--ll-accent, #0969da)",
+        fontWeight: 600,
+        textDecoration: "none",
+      }}
+      onMouseEnter={(e) => {
+        e.currentTarget.style.textDecoration = "underline";
+      }}
+      onMouseLeave={(e) => {
+        e.currentTarget.style.textDecoration = "none";
+      }}
+    >
+      {children}
+    </a>
+  );
+}
+
 export function Code({ children }: { children: React.ReactNode }) {
   return (
     <code className="ll-inline-code">
@@ -278,6 +301,25 @@ export function Section({ id, title, children }: { id: string; title: string; ch
   );
 }
 
+export function OL({ children }: { children: React.ReactNode }) {
+  return (
+    <ol
+      className="m-0 pl-5"
+      style={{
+        fontFamily: "var(--ll-font-primary)",
+        fontSize: "14px",
+        fontWeight: 475,
+        lineHeight: "20px",
+        letterSpacing: "-0.09px",
+        color: "var(--ll-text-primary)",
+        listStyleType: "decimal",
+      }}
+    >
+      {children}
+    </ol>
+  );
+}
+
 export function List({ children }: { children: React.ReactNode }) {
   return (
     <ul
@@ -564,7 +606,6 @@ export function EditorialPage({
         textRendering: "optimizeLegibility",
       }}
     >
-      <BackButton />
       <TableOfContents items={toc} logo={logo} />
 
       <div