Add AGPL application notice to LICENSE

[codeforester]

Summary

• Add a Banyan Labs-specific AGPL application notice to the top of LICENSE.
• Keep the GNU AGPL v3 license text intact underneath.

Issue

Fixes #62

Validation

• grep -Fq "Copyright (C) 2026 Ramesh Padmanabhaiah" LICENSE
• git diff --check
• git diff --cached --check

Demo Impact

None. Documentation/license text only.

Notes

• The AGPL "How to Apply These Terms to Your New Programs" appendix remains unchanged, including its template placeholders, because it is part of the official license document.
• Project status could not be updated through basectl gh because the local gh token is invalid; issue and PR creation used the GitHub connector instead.