docs: license alignment across repos (#10)

## Summary
- Fix README license section: was incorrectly stating Apache 2.0, actual
LICENSE file is AGPL-3.0
- Add dual licensing mention for commercial use
- Add CLA reference

## Test plan
- [x] Verify LICENSE file is AGPL-3.0
- [x] README now matches

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: StevenJohnson998

README.md

@@ -224,7 +224,9 @@ All contributions are welcome, from spec feedback to code to documentation.
 
 ## License
 
-Apache 2.0 — see [LICENSE](LICENSE).
+AGPLv3 — see [LICENSE](LICENSE). Dual licensing available for commercial use, [reach out](https://github.com/StevenJohnson998/AgentLedger/issues).
+
+Contributors must sign a [Contributor License Agreement](CLA.md).
 
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