Revamp docs homepage; remove subpages

Consolidate documentation into a single one-page site: add one-pager styles (hero, install strip, lead, footer, etc.) to docs/assets/stylesheets/homebrew-legacy.css, update docs/index.html with a simplified landing/hero, streamlined nav and usage examples, and delete the separate docs pages (cli, concepts, faq, install). This centralizes content, reduces duplication, and updates messaging and install flow for the docs site.

Author: CptPlastic

docs/assets/stylesheets/homebrew-legacy.css

@@ -458,3 +458,91 @@ h3 {
     grid-template-columns: 1fr;
   }
 }
+
+/* ── one-pager ── */
+
+.hero {
+  text-align: center;
+  padding: 4.5rem 2rem 1.5rem;
+  width: 100%;
+  max-width: 660px;
+}
+
+.hero h1 {
+  margin: 0.4rem 0 0;
+  font-size: clamp(3rem, 9vw, 5.5rem);
+  font-weight: 900;
+  color: var(--gold-bright);
+  text-shadow: 0 0 40px rgba(232, 184, 75, 0.4), 2px 2px 0 rgba(0, 0, 0, 0.5);
+  letter-spacing: 0.08em;
+  line-height: 1.1;
+}
+
+.hero .tagline {
+  font-style: italic;
+  color: var(--parchment-dark);
+  font-size: 1.18rem;
+  margin: 1.1rem auto 0;
+  opacity: 0.85;
+  max-width: 34rem;
+  line-height: 1.6;
+}
+
+.install-strip {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  margin: 2rem auto 0;
+  max-width: 360px;
+  width: 100%;
+  gap: 0;
+}
+
+.incantation.one-liner {
+  width: 100%;
+  text-align: center;
+  padding: 0.85rem 1.5rem;
+  margin: 0;
+}
+
+.install-then {
+  font-family: "Cinzel", serif;
+  font-size: 0.7rem;
+  letter-spacing: 0.2em;
+  text-transform: uppercase;
+  color: var(--gold);
+  opacity: 0.55;
+  padding: 0.3rem 0;
+}
+
+.lead {
+  font-size: 1.12rem;
+  color: var(--ink);
+  margin-bottom: 1.5rem;
+  line-height: 1.72;
+}
+
+.site-footer {
+  text-align: center;
+  color: rgba(200, 151, 58, 0.45);
+  font-family: "Cinzel", serif;
+  font-size: 0.78rem;
+  letter-spacing: 0.15em;
+  margin-top: 1rem;
+  padding-top: 2rem;
+  border-top: 1px solid rgba(200, 151, 58, 0.2);
+  width: 100%;
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  gap: 0.85rem;
+}
+
+.site-footer a {
+  color: rgba(200, 151, 58, 0.6);
+  text-decoration: none;
+}
+
+.site-footer a:hover {
+  color: var(--gold-bright);
+}