docs: document project sponsorship roles (#29)

## Summary

- add a dedicated sponsor policy and recognition page
- separate sponsorship from maintainership and project governance
- protect contract, privacy, conformance, and evidence semantics from
sponsor influence
- link the policy from the repository overview

## Validation

- `git diff --check`

Signed-off-by: Imran Siddique <45405841+imran-siddique@users.noreply.github.com>

Author: imran-siddique

README.md

@@ -129,6 +129,7 @@ python examples/governed_workflow.py
 - [Roadmap](ROADMAP.md)
 - [Security](SECURITY.md)
 - [Governance](GOVERNANCE.md)
+- [Sponsors](SPONSORS.md)
 - [Releasing](RELEASING.md)
 - [Contributing](CONTRIBUTING.md)
 

SPONSORS.md

@@ -0,0 +1,19 @@
+# Sponsors
+
+AgentTrust Telemetry is an open-source AgenTrust project. Sponsors provide
+funding, engineering time, infrastructure, or other in-kind support.
+Sponsorship does not confer project ownership, governance authority, or control
+over technical decisions.
+
+## Current sponsors
+
+### OPAQUE Systems
+
+Founding engineering and infrastructure sponsor, and contributor to the
+AgenTrust telemetry ecosystem.
+
+## Recognition policy
+
+Sponsor recognition is separate from maintainership and governance. Sponsors
+receive no authority over the telemetry contract, privacy profile, conformance
+fixtures, compatibility claims, or evidence semantics.