Make an "Installation" and/or "Setup your environment" page(s), which would describe how to install and setup tooling locally

[novusnota]

Should be placed right before the "Fundamentals of Tact" and should be referenced from the index page of the docs.

References:

• https://solana.com/docs/intro/installation
• https://bun.sh/docs/installation
• https://docs.deno.com/runtime/getting_started/installation/
• https://docs.deno.com/runtime/getting_started/setup_your_environment/

[novusnota]

And should also have a brief description of llms.txt and related, with their usage in Cursor/etc.

See #2763.

[novusnota]

And should also add cross-links from the README.md descriptions of the formatter and the disassembler.