Added onboarding cli for bindu

[Avngrstark62]

Problem

Current onboarding via Cookiecutter is slow and high-friction:

• many prompts
• manual .env setup
• multiple steps

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Solution

Introduce a CLI command:

uvx bindu onboard

This reduces onboarding to a single command and minimal prompts.

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What it does

• wraps Cookiecutter (non-interactive)
• asks only essential inputs
• auto-generates project
• creates .env
• runs uv sync
• outputs run command

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Impact

• reduces setup from multiple steps → 1 command
• removes unnecessary prompts
• improves first-time user experience

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Notes

• Cookiecutter still used internally (can be replaced later)

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Feedback welcome on UX and flow.

[Avngrstark62]

here's the video of how the onboarding looks like now...

Screencast.from.2026-03-18.20-25-20.webm