[P0] Prove framework neutrality with a non-LangGraph managed Agent

[0YHR0]

Problem

Framework neutrality is currently a design claim. Without a runnable non-LangGraph Agent, users
can reasonably treat AgentMesh as a LangGraph application platform.

Proposal

Implement one minimal Generic Worker Adapter and an independently packaged reference Agent that
does not import LangGraph. It may communicate over a bounded local subprocess protocol first, but
must use the same Agent Registry, Task/Run/Attempt, policy, budget, Artifact, audit, cancellation,
and recovery surfaces as the LangGraph adapter.

The reference workload should create a concrete deliverable and deliberately exercise one retry or
process-restart path. Its purpose is contract proof, not a new vertical scenario.

Acceptance criteria

• The reference Agent is built and tested independently from AgentMesh internals.
• It registers a runtime descriptor and is selected through normal capability matching.
• One task runs end to end with no LangGraph package imported in the Agent process.
• Cancellation, timeout, duplicate assignment, Agent process death, and restart converge.
• Output is an immutable Artifact with runtime/version/Attempt lineage and usage evidence.
• Console and APIs show both LangGraph and generic runtimes without special-case UI branches.
• CI runs the generic adapter conformance test.

Non-goals

• Building native adapters for every popular Agent framework.
• Embedding a coding Agent or desktop automation harness in core.
• Allowing the external Agent direct database access.

Dependencies

Blocked by Managed Agent Runtime API v0.1.

[0YHR0]

PR #144 defines the non-LangGraph proof as A3: a constrained generic subprocess adapter and deterministic reference Agent, required to pass the same Runtime conformance suite as LangGraph.