feat: use fumadoc 15 + tailwind 4 (#1690)

apps/next/package.json

apps/next/postcss.config.js

apps/next/postcss.config.mjs

apps/next/scripts/generate-docs.mts

apps/next/scripts/update-llamacloud.mts

apps/next/src/app/global.css

apps/next/src/components/code-block.tsx

apps/next/src/components/demo/chat/api/demo.tsx

apps/next/src/components/demo/chat/rsc/chat-section.tsx

...c/content/docs/llamaindex/guide/agents/2_create_agent.mdx

.../content/docs/llamaindex/guide/agents/5_rag_and_tools.mdx

apps/next/src/content/docs/llamaindex/guide/chat/chat.mdx

apps/next/src/content/docs/llamaindex/guide/chat/install.mdx

apps/next/src/content/docs/llamaindex/guide/chat/meta.json

apps/next/src/content/docs/llamaindex/guide/chat/rsc.mdx

...t/docs/llamaindex/modules/llms/available_llms/bedrock.mdx

apps/next/src/content/docs/llamaindex/modules/tool/index.mdx

apps/next/tailwind.config.mjs

e2e/examples/cloudflare-hono/package.json

e2e/examples/cloudflare-worker-agent/package.json