personal memory agent

Relicense project to AGPL-3.0-only master

- Add official AGPL-3.0 LICENSE from gnu.org - Add CONTRIBUTING.md with DCO sign-off requirement - Update pyproject.toml license field and classifier - Update README with sol pbc attribution and AGPL license section - Update docs/VENDOR.md to reference AGPL-compatible licenses - Add SPDX-License-Identifier headers to all 188 source files 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>


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193 changed files