feat: add official Codex skill and harden task execution

Install and update artemis-use with task diagnostics and plugin guidance. Preserve cross-device file receipts, review canonical reports, guard stage transitions and reduce small history summaries. Improve exploration lifecycle, request recovery and browser live connections.

artemis/plugins/delivery.py

@@ -0,0 +1,62 @@
+"""Model-facing runtime receipts, outside the truncatable plugin observation."""
+
+import json
+
+from artemis.plugins.prompt_budget import bounded_result_text
+
+
+def attachment_fields(attachments: list) -> list[dict]:
+    return [
+        {
+            key: value[:1000] if isinstance(value, str) else value
+            for key in ("path", "name", "bytes", "sha256", "media_type")
+            if isinstance(value := item.get(key), (str, int))
+        }
+        for item in attachments[:8]
+        if isinstance(item, dict)
+    ]
+
+
+def step_attachment_receipts(step: dict) -> str:
+    """Keep actual exported paths through every history compaction level."""
+    result = step.get("last_execution_result")
+    actions = result.get("execution") if isinstance(result, dict) else None
+    if not isinstance(actions, list):
+        actions = step.get("action_taken")
+    actions = actions if isinstance(actions, list) else [actions]
+    rows = []
+    for action in actions:
+        if not isinstance(action, dict) or not action.get("plugin_id"):
+            continue
+        attachments = action.get("attachments")
+        if isinstance(attachments, list) and attachments:
+            rows.append(
+                {
+                    "plugin": action["plugin_id"],
+                    "attachments": attachment_fields(attachments),
+                    **({"omitted": len(attachments) - 8} if len(attachments) > 8 else {}),
+                }
+            )
+    return json.dumps(rows, ensure_ascii=False) if rows else ""
+
+
+def result_blocks(text: str, *, call_id: str = "", attachments=None) -> list[dict]:
+    blocks = []
+    if isinstance(attachments, list) and attachments:
+        # Only callers holding runtime-validated metadata may supply these.
+        # Never extract alleged receipts from plugin prose/structured_content.
+        receipts = attachment_fields(attachments)
+        receipt = {"attachments": receipts}
+        if len(attachments) > 8:
+            receipt["omitted"] = len(attachments) - 8
+        blocks.append(
+            {
+                "type": "text",
+                "text": (
+                    "ARTEMIS verified file receipts (task trace paths; content correctness is not verified):\n"
+                    + json.dumps(receipt, ensure_ascii=False)
+                ),
+            }
+        )
+    blocks.append({"type": "text", "text": bounded_result_text(text, call_id=call_id)})
+    return blocks