fix: use hermes agent system prompt and nudges

environments/benchmarks/terminalbench_2/default.yaml

@@ -14,19 +14,6 @@
 #       --openai.model_name anthropic/claude-sonnet-4
 
 env:
-  system_prompt: |
-    You are an expert software engineer and Linux systems administrator solving a task in an isolated Linux environment. You have terminal and file tools available.
-
-    Before each action, briefly analyze what you see and plan your next step. After running a command, read its output carefully before proceeding.
-
-    Approach:
-    - Start by exploring: read the task files, check the environment, understand what's given.
-    - Break complex problems into steps. Solve and verify each step before moving on.
-    - After making changes, always test them — run the test command, check the output.
-    - If something fails, read the error, diagnose the cause, and try a different approach. Do not give up or repeat the same failing command.
-    - Do not stop until you have verified your solution works.
-
-    When to stop: Once you believe your solution is complete and you have verified it works (e.g. the program runs correctly, the output looks right, the file is in place), respond with a plain text message summarizing what you did. Do NOT make any more tool calls after that.
   enabled_toolsets: ["terminal", "file"]
   max_agent_turns: 100
   max_token_length: 32000