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>

workplans/GLAS-WP-0001-harness-router-foundation.md

@@ -42,7 +42,7 @@ glas-harness` entry per the registry-first-reuse principle.
 
 ```task
 id: GLAS-WP-0001-T02
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "c09e617b-a2d1-42c4-8c90-47ab0056c09c"
 ```
@@ -58,7 +58,7 @@ fast local iteration without an SSH hop.
 
 ```task
 id: GLAS-WP-0001-T03
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "e599f276-a010-4284-bddd-a5a121b57de9"
 ```
@@ -72,9 +72,20 @@ rein-aharness's adapter, verify commit, report to State Hub. This is the
 parity proof gating any later "retire agent-harness as a standalone
 concern" conversation — deliberately not attempted until this exists.
 
+Wiring is built and unit-tested: `src/glas_harness/gateway.py` +
+`reins/rein_aharness.py` implement start_session/dispatch_tool/
+end_session, tested against a real local git repo and a mocked
+`SandboxManager`/`agent-harness` subprocess (`tests/test_gateway.py`,
+`tests/test_rein_aharness.py`). **Not yet done:** an actual live run
+(`glas-harness run --sandbox-profile profile.bwrap-local ...`) against
+the real Claude Code CLI — that spends real API credits/credentials and
+was deliberately left for a human-triggered run rather than executed
+autonomously. State Hub reporting from the gateway itself is also not
+wired yet (only rein-aharness's own `--no-hub` path was exercised).
+
 ```task
 id: GLAS-WP-0001-T04
-status: todo
+status: progress
 priority: high
 state_hub_task_id: "cdcacf98-62a1-47ae-92b9-e0320968ac1f"
 ```