fix(workflows): enable interactive workflow resume after approval gate

.archon/commands/e2e-echo-command.md

@@ -0,0 +1,13 @@
+---
+description: E2E test command — echoes back the user message
+argument-hint: <any text>
+---
+
+# E2E Echo Command
+
+You are a simple echo agent for testing. Your ONLY job is to repeat back the user's message.
+
+User message: $ARGUMENTS
+
+Respond with EXACTLY this format and nothing else:
+command-echo: <the user message above>

.archon/scripts/echo-args.py

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+"""Simple script node test — echoes input as JSON (uv/Python runtime)."""
+import json
+import sys
+from datetime import datetime, timezone
+
+input_val = sys.argv[1] if len(sys.argv) > 1 else "no-input"
+print(json.dumps({"echoed": input_val, "timestamp": datetime.now(timezone.utc).isoformat()}))

.archon/test-fixtures/mcp/e2e-filesystem.json

@@ -0,0 +1,6 @@
+{
+  "filesystem": {
+    "command": "npx",
+    "args": ["-y", "@modelcontextprotocol/server-filesystem", "/tmp"]
+  }
+}