feat(mcpedia): Phase 1 MVP — monorepo, Core, Web UI, MCP server, Postgres FTS

- bun workspaces + Turborepo monorepo (apps/web, apps/mcp; packages/*, scripts)
- @mcpedia/core single business-logic layer (Document/Content/Search services)
- @mcpedia/db Drizzle schema: documents + weighted tsvector (GIN) for FTS
- @mcpedia/parser frontmatter, @mcpedia/search Postgres FTS (ts_rank+ts_headline)
- Next.js 16 Web UI (home/doc SSG, search dynamic) + react-markdown render
- MCP server (stdio) with 4 tools + in-memory smoke test
- scripts/indexer walks content/ -> upserts into Postgres
- 4 seed docs; README + PHASES status

apps/web/app/components/Markdown.tsx

@@ -0,0 +1,9 @@
+import ReactMarkdown from "react-markdown";
+
+export default function Markdown({ source }: { source: string }) {
+  return (
+    <div className="prose prose-zinc dark:prose-invert max-w-none [&_pre]:bg-zinc-100 dark:[&_pre]:bg-zinc-900 [&_pre]:p-3 [&_pre]:rounded [&_code]:font-mono [&_a]:underline">
+      <ReactMarkdown>{source}</ReactMarkdown>
+    </div>
+  );
+}