docs: update stale dx help output in 0.7 tutorial

[WaterWhisperer]

While continuing to follow the docs after #661, I noticed the 0.7 tutorial tooling page still showed an older dx help output with clean and without 0.7 commands like doctor, print, self-update, tools, and components. This updates the tutorial snippet to match the existing 0.7 Tools guide output.

[WaterWhisperer]

Also noticed /learn/0.7/tutorial/new_app still embeds /assets/06_docs/dx_new_06.mp4.

That video looks outdated: it shows Tailwind CSS: false and does not include the newer prompts for LLMs prompt, while the 0.7 text says TailwindCSS: true, prompts for LLMs: false, and Web.

Not fixing it here since replacing the video should probably match the existing recording style.

Supplement

• /tutorial/new_app uses /assets/06_docs/dx_new_06.mp4, which shows an older dx new flow.
• /tutorial/rsx uses /assets/06_docs/unstyled_dog_app.png, whose editor screenshot does not include the id attributes shown in the current code. The next CSS page relies on those ids.