feat(web): site chrome on /blog + distinct content link color

- Add SiteShell (rail nav + workspace + footer) and wrap /blog and
  /blog/[slug] in it so they share the site's dark chrome instead of
  rendering as bare standalone pages.
- Style rendered post HTML (.blog-content) for the dark workspace.
- Links were `color: inherit` everywhere, so content-area links matched
  body text and were invisible. Give links a distinct accent (#5ac8a6);
  keep the rail nav and buttons on their own colors.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/logicsrc-web/src/components/site-shell.tsx

@@ -0,0 +1,79 @@
+import type { ReactNode } from "react";
+
+// Mirrors the rail/nav from page-markup.ts so standalone routes (e.g. /blog)
+// share the site chrome. Anchor links point at the homepage sections.
+const NAV: Array<{ href: string; label: string }> = [
+  { href: "/#overview", label: "Overview" },
+  { href: "/#schemas", label: "Schemas" },
+  { href: "/agent-swarm", label: "Soon" },
+  { href: "/agentbyte", label: "AgentByte" },
+  { href: "/credential-sharing", label: "Credentials" },
+  { href: "/#cli", label: "CLI" },
+  { href: "/docs", label: "Docs" },
+  { href: "/blog", label: "Blog" },
+  { href: "/openspec", label: "OpenSpec" },
+  { href: "/hire-us", label: "Hire Us" },
+  { href: "/about", label: "About" },
+  { href: "/terms", label: "Terms" },
+  { href: "/privacy", label: "Privacy" },
+  { href: "/#reference", label: "Reference" },
+];
+
+export function SiteShell({
+  children,
+  active,
+}: {
+  children: ReactNode;
+  active?: string;
+}): ReactNode {
+  return (
+    <main className="shell">
+      <aside className="rail">
+        <a className="brand" href="/" style={{ textDecoration: "none", color: "inherit" }}>
+          <span className="mark">LS</span>
+          <div>
+            <strong>LogicSRC</strong>
+            <small>Open coordination standards</small>
+          </div>
+        </a>
+        <nav aria-label="LogicSRC sections">
+          {NAV.map((item) => (
+            <a
+              key={item.href}
+              href={item.href}
+              className={item.label === active ? "active" : undefined}
+              aria-current={item.label === active ? "page" : undefined}
+            >
+              {item.label}
+            </a>
+          ))}
+        </nav>
+      </aside>
+      <section className="workspace">
+        {children}
+        <footer
+          style={{
+            maxWidth: "72rem",
+            margin: "2rem auto 0",
+            padding: "1.25rem 0",
+            borderTop: "1px solid rgba(245, 247, 244, 0.12)",
+            display: "flex",
+            flexWrap: "wrap",
+            gap: "0.75rem",
+            justifyContent: "space-between",
+            fontSize: "0.85rem",
+            color: "#b5beb2",
+          }}
+        >
+          <span>© {new Date().getFullYear()} Profullstack, Inc. · LogicSRC</span>
+          <span style={{ display: "flex", gap: "0.75rem" }}>
+            <a href="/docs" style={{ color: "inherit" }}>Docs</a>
+            <a href="/blog/rss.xml" style={{ color: "inherit" }}>RSS</a>
+            <a href="/terms" style={{ color: "inherit" }}>Terms</a>
+            <a href="/privacy" style={{ color: "inherit" }}>Privacy</a>
+          </span>
+        </footer>
+      </section>
+    </main>
+  );
+}