fix(website): SEO canonicals, host redirects, sitemap, app noindex

Addresses the high-volume issues from the Ahrefs audit:
- Worker entrypoint 301s every request not on https://paseo.sh
  (www subdomain and http variants), killing the duplicate-page
  errors and the HTTP→HTTPS internal-link notices.
- pageMeta() emits <link rel="canonical"> and og:url per route;
  every head() call now passes its canonical path.
- /blog stops rewriting itself to /blog?drafts=false; the search
  param only appears when explicitly true.
- Sitemap includes /blog and each post.
- Trim homepage title under SERP truncation, rewrite /agents meta
  description under 160 chars, pad short descriptions on
  /privacy, /download, /cloud, /changelog, /docs.
- app.paseo.sh gets <meta robots=noindex,nofollow> and a
  Disallow-all robots.txt so the SPA shell stops polluting the
  crawl with H1-missing / no-OG / low-word-count warnings.

packages/website/src/routes/blog/$.tsx

@@ -6,11 +6,10 @@ import { pageMeta } from "~/meta";
 export const Route = createFileRoute("/blog/$")({
   head: ({ params }) => {
     const slug = params._splat ?? "";
+    const path = `/blog/${slug}`;
     const post = getPost(slug);
-    if (!post) return { meta: pageMeta("Not Found - Paseo", "Post not found.") };
-    return {
-      meta: pageMeta(`${post.frontmatter.title} - Paseo`, post.frontmatter.description),
-    };
+    if (!post) return pageMeta("Not Found - Paseo", "Post not found.", path);
+    return pageMeta(`${post.frontmatter.title} - Paseo`, post.frontmatter.description, path);
   },
   component: BlogPost,
 });

packages/website/src/routes/blog/index.tsx

@@ -3,13 +3,21 @@ import { createFileRoute, Link } from "@tanstack/react-router";
 import { getPosts, formatDate } from "~/posts";
 import { pageMeta } from "~/meta";
 
+interface BlogSearch {
+  drafts?: true;
+}
+
 export const Route = createFileRoute("/blog/")({
-  validateSearch: (search: Record<string, unknown>) => ({
-    drafts: search.drafts === true || search.drafts === "" || search.drafts === "true",
-  }),
-  head: () => ({
-    meta: pageMeta("Blog - Paseo", "Updates, thoughts, and announcements from the Paseo team."),
-  }),
+  validateSearch: (search: Record<string, unknown>): BlogSearch => {
+    const drafts = search.drafts === true || search.drafts === "" || search.drafts === "true";
+    return drafts ? { drafts: true } : {};
+  },
+  head: () =>
+    pageMeta(
+      "Blog – Updates and announcements from the Paseo team",
+      "Product updates, technical posts, and announcements from the Paseo team. Notes on building a self-hosted, multi-agent dev environment for your phone.",
+      "/blog",
+    ),
   component: BlogIndex,
 });
 
@@ -43,7 +51,7 @@ function PostRow({ slug, title, date, draft }: PostRowProps) {
 
 function BlogIndex() {
   const { drafts } = Route.useSearch();
-  const posts = getPosts(drafts);
+  const posts = getPosts(drafts === true);
 
   return (
     <div>