fix(sandbox): update Tenki SDKs and drop removed project_id (#18117)

### Summary

Brings both halves of the Tenki sandbox provider onto current SDKs and
removes `project_id`, which Tenki deleted from its API.

**Go:** `github.com/LuxorLabs/tenki-sdk-go/sandbox` `v0.5.2` → `v0.7.0`
(current latest).
**Python:** the provider's SDK was renamed on PyPI — `tenki-sandbox` is
frozen at 0.4.0 and everything from 0.5 ships as
[`tenki`](https://pypi.org/project/tenki/). The docs told operators to
`pip install tenki-sandbox`, which installs a stale SDK that no longer
matches this provider's expectations.

**`project_id` is gone.** Tenki removed project scoping from the sandbox
API in 0.5.x: `Client.create()` no longer accepts `project_id`, so the
current code path would raise `TypeError` against a current SDK. It was
also marked `required: True` in the config schema, so the Admin >
Sandbox Settings form asked for a value that no longer exists.

test/unit_test/agent/sandbox/test_tenki_provider.py

@@ -125,7 +125,6 @@ class _FakeClient:
 def _build_provider(sandbox: _FakeSandbox, monkeypatch) -> tuple[TenkiProvider, _FakeClient]:
     provider = TenkiProvider()
     provider.api_key = "tk_test"
-    provider.project_id = "proj-1"
     provider.timeout = 30
     provider.max_output_bytes = 1024 * 1024
     provider.max_artifacts = 20
@@ -227,7 +226,7 @@ def test_tenki_provider_create_passes_project_and_outbound(monkeypatch):
 
     provider.create_instance("python")
 
-    assert client.create_kwargs["project_id"] == "proj-1"
+    assert "project_id" not in client.create_kwargs
     assert client.create_kwargs["allow_outbound"] is True
     assert client.create_kwargs["image"] == "my-image"
     assert client.create_kwargs["cpu_cores"] == 4
@@ -237,12 +236,12 @@ def test_tenki_provider_config_schema_and_validation():
     schema = TenkiProvider.get_config_schema()
     assert schema["api_key"]["required"] is True
     assert schema["api_key"]["secret"] is True
-    assert schema["project_id"]["required"] is True
+    assert "project_id" not in schema
 
     provider = TenkiProvider()
-    ok, _ = provider.validate_config({"api_key": "tk", "project_id": "p", "timeout": 30, "max_lifetime": 3600, "max_output_bytes": 1024, "max_artifacts": 5, "max_artifact_bytes": 1024})
+    ok, _ = provider.validate_config({"api_key": "tk", "timeout": 30, "max_lifetime": 3600, "max_output_bytes": 1024, "max_artifacts": 5, "max_artifact_bytes": 1024})
     assert ok is True
-    bad, msg = provider.validate_config({"api_key": "", "project_id": "p"})
+    bad, msg = provider.validate_config({"api_key": ""})
     assert bad is False
     assert "API key" in msg
 
@@ -262,7 +261,7 @@ def test_tenki_provider_initialize_maps_auth_error(monkeypatch):
     monkeypatch.setattr(provider, "_create_client", lambda: _UnauthorizedClient())
 
     with pytest.raises(SandboxProviderConfigError, match="authentication failed"):
-        provider.initialize({"api_key": "tk_bad", "project_id": "proj-1"})
+        provider.initialize({"api_key": "tk_bad"})
 
 
 def test_tenki_provider_instances_are_independent(monkeypatch):
@@ -277,7 +276,6 @@ def test_tenki_provider_instances_are_independent(monkeypatch):
 
     provider = TenkiProvider()
     provider.api_key = "tk_test"
-    provider.project_id = "proj-1"
     provider.timeout = 30
     provider._initialized = True
     provider._client = _MultiClient(None)