Implement the harness contract and prove it against rein-aharness (GLAS-WP-0001-T02/T03/T04)

- src/glas_harness/contract.py: Rein ABC (start_session/dispatch_tool/
  end_session), SandboxHandle/ToolCall/ToolResult, per docs/harness-contract.md.
- reins/rein_aharness.py: adapter around the rein-aharness CLI. Collapses
  a whole `agent-harness run` into one dispatch_tool call for now (no
  per-tool hooks yet — tracked in rein-aharness HARNESS-WP-0002-T03);
  verifies success via new-commit detection, mirroring rein-aharness's
  own success signal.
- gateway.py + cli.py: resolves a sand-boxer sandbox, runs one task
  through a rein, tears the sandbox down.
- registry/reins/*.yaml (rein-aharness implemented, rein-openweights
  planned) and profiles/harness.agent-dev{,-local}.yaml, pairing with
  sand-boxer's profile.agent-dev and the new profile.bwrap-local.

Tested against a real local git repo + mocked SandboxManager/CLI
subprocess (10 tests, all passing). A real live run against the actual
Claude Code CLI is deliberately left for a human-triggered follow-up —
not executed autonomously since it spends real API credits/credentials.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

registry/reins/rein-aharness.yaml

@@ -0,0 +1,16 @@
+id: rein-aharness
+title: Claude Code CLI rein
+description: >
+  Governed, unattended/scheduled harness driving Claude Code CLI sessions.
+  Renamed from agent-harness (ADR-001). Deployed on Railiance for tenant
+  binky-control.
+handler: glas_harness.reins.rein_aharness:ReinAharness
+capabilities:
+  session_style: unattended
+  model_class: frontier
+  credential_source: rein-local
+  # rein-local: kaizen-agentic (blueprints), activity-core/issue-core
+  # (intake), OpenBao/ops-warden (credentials) — see
+  # rein-aharness/workplans/HARNESS-WP-0002-T04 for whether this stays
+  # rein-local or moves into glas-harness.
+status: implemented

registry/reins/rein-openweights.yaml

@@ -0,0 +1,13 @@
+id: rein-openweights
+title: OpenRouter open-weight agentic loop
+description: >
+  Agentic tool-use harness driving current open-weight models via
+  OpenRouter/llm-connect, as an alternative to frontier-vendor CLIs.
+  Chartered by ADR-001; not yet implementing this contract.
+handler: glas_harness.reins.rein_openweights:ReinOpenWeights
+capabilities:
+  session_style: unattended
+  model_class: open-weight
+  credential_source: tbd
+  # tbd: resolved by GLAS-WP-0001-T06 before this rein is implemented.
+status: planned