fix: lazy-import harness agents, add version-pinned SG mirrors

- Make harness agent imports (codex, cursor, gemini, copilot, openhands)
  lazy so the agents package works without harbor installed. This allows
  local scripts to use metrics/config modules without Docker.
- Add 4 version-pinned SG mirrors to instance_to_mirror.json:
  envoy v1.30.0/v1.31.0 and terraform v1.9.0/v1.10.0 for multi-version
  comparison tasks (envoy-migration, terraform-arch).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: sjarmak

agents/__init__.py

@@ -41,13 +41,9 @@
     create_example_config,
 )
 
-from .harnesses import (
-    CodexHarnessAgent,
-    CopilotHarnessAgent,
-    CursorHarnessAgent,
-    GeminiHarnessAgent,
-    OpenHandsHarnessAgent,
-)
+# Harness agents require the ``harbor`` package (only available inside
+# Docker containers).  They are re-exported via __getattr__ so the rest
+# of this package works without harbor installed.
 
 __all__ = [
     # Metrics extraction
@@ -78,10 +74,26 @@
     "parse_ablation_config",
     "create_example_config",
 
-    # Harness agents
+    # Harness agents (lazy-imported, require harbor)
     "CodexHarnessAgent",
     "CopilotHarnessAgent",
     "CursorHarnessAgent",
     "GeminiHarnessAgent",
     "OpenHandsHarnessAgent",
 ]
+
+
+_HARNESS_AGENTS = {
+    "CodexHarnessAgent",
+    "CopilotHarnessAgent",
+    "CursorHarnessAgent",
+    "GeminiHarnessAgent",
+    "OpenHandsHarnessAgent",
+}
+
+
+def __getattr__(name):
+    if name in _HARNESS_AGENTS:
+        from . import harnesses
+        return getattr(harnesses, name)
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")

agents/harnesses/__init__.py

@@ -1,10 +1,9 @@
-"""Harness-specific agent implementations."""
+"""Harness-specific agent implementations.
 
-from .codex import CodexHarnessAgent
-from .copilot import CopilotHarnessAgent
-from .cursor import CursorHarnessAgent
-from .gemini import GeminiHarnessAgent
-from .openhands import OpenHandsHarnessAgent
+These agents depend on the ``harbor`` package which is only available
+inside Docker containers.  The imports are deferred so that the rest of
+the ``agents`` package can be used without harbor installed.
+"""
 
 __all__ = [
     "CodexHarnessAgent",
@@ -13,3 +12,19 @@
     "GeminiHarnessAgent",
     "OpenHandsHarnessAgent",
 ]
+
+
+def __getattr__(name):
+    """Lazy-import harness agents so harbor is only required at use time."""
+    _map = {
+        "CodexHarnessAgent": ".codex",
+        "CopilotHarnessAgent": ".copilot",
+        "CursorHarnessAgent": ".cursor",
+        "GeminiHarnessAgent": ".gemini",
+        "OpenHandsHarnessAgent": ".openhands",
+    }
+    if name in _map:
+        import importlib
+        mod = importlib.import_module(_map[name], package=__name__)
+        return getattr(mod, name)
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")

configs/instance_to_mirror.json

@@ -591,6 +591,45 @@
   "ccb_dependeval/multifile_editing-java-e1c422ed": "sg-benchmarks/dependeval-java-me-e1c422ed",
   "ccb_dependeval/multifile_editing-python-ea840a03": "sg-benchmarks/dependeval-python-me-ea840a03",
   "ccb_dependeval/dependency_recognition-javascript-ef7ab7e5": "sg-benchmarks/dependeval-javascript-dr-ef7ab7e5",
+  "version_pinned": {
+    "_note": "Version-pinned mirrors for multi-version comparison tasks (e.g. migration doc-gen). Each version has its own mirror.",
+    "envoy": {
+      "v1.30.0": {
+        "repo": "envoyproxy/envoy",
+        "mirror_name": "sg-benchmarks/envoy--50ea83e6",
+        "commit": "50ea83e602d5da162df89fd5798301e22f5540cf",
+        "tag": "v1.30.0",
+        "indexed": true,
+        "used_by": ["envoy-migration-doc-gen-001"]
+      },
+      "v1.31.0": {
+        "repo": "envoyproxy/envoy",
+        "mirror_name": "sg-benchmarks/envoy--7b8baff1",
+        "commit": "7b8baff1758f0a584dcc3cb657b5032000bcb3d7",
+        "tag": "v1.31.0",
+        "indexed": true,
+        "used_by": ["envoy-migration-doc-gen-001"]
+      }
+    },
+    "terraform": {
+      "v1.9.0": {
+        "repo": "hashicorp/terraform",
+        "mirror_name": "sg-benchmarks/terraform--7637a921",
+        "commit": "7637a9216e68f2812887eaf0722f9d3f9804c45e",
+        "tag": "v1.9.0",
+        "indexed": true,
+        "used_by": ["terraform-arch-doc-gen-001"]
+      },
+      "v1.10.0": {
+        "repo": "hashicorp/terraform",
+        "mirror_name": "sg-benchmarks/terraform--24236f4f",
+        "commit": "24236f4f0bd10ada71d70868abe15f9d88099747",
+        "tag": "v1.10.0",
+        "indexed": true,
+        "used_by": ["terraform-arch-doc-gen-001"]
+      }
+    }
+  },
   "investigation": {
     "_note": "Investigation tasks use major public repos directly indexed on Sourcegraph. No custom mirrors needed.",
     "tasks": {