Docs: verify the Windows source-build quickstart on a clean machine

[Codewriter90x]

Goal

Verify the documented Windows source-build path on a clean machine and report any missing or ambiguous step.

Scope

• follow the repository prerequisites and quick-start documentation;
• use the pinned Unity and .NET versions;
• record the commands that succeed or fail;
• propose documentation-only corrections.

Acceptance criteria

• The exact Windows version and tool versions are listed.
• The repository builds from a fresh clone, or the first reproducible blocker is documented.
• Any proposed fix updates only public documentation.
• Logs are sanitized: no usernames, home paths, tokens, device identifiers, or private project data.

No Unity player binary needs to be uploaded.