refactor: add tool_error/tool_result helpers + read_raw_config, migrate 129 callsites

Add three reusable helpers to eliminate pervasive boilerplate:

tools/registry.py — tool_error() and tool_result():
  Every tool handler returns JSON strings. The pattern
  json.dumps({"error": msg}, ensure_ascii=False) appeared 106 times,
  and json.dumps({"success": False, "error": msg}, ...) another 23.
  Now: tool_error(msg) or tool_error(msg, success=False).

  tool_result() handles arbitrary result dicts:
  tool_result(success=True, data=payload) or tool_result(some_dict).

hermes_cli/config.py — read_raw_config():
  Lightweight YAML reader that returns the raw config dict without
  load_config()'s deep-merge + migration overhead. Available for
  callsites that just need a single config value.

Migration (129 callsites across 32 files):
- tools/: browser_camofox (18), file_tools (10), homeassistant (8),
  web_tools (7), skill_manager (7), cronjob (11), code_execution (4),
  delegate (5), send_message (4), tts (4), memory (7), session_search (3),
  mcp (2), clarify (2), skills_tool (3), todo (1), vision (1),
  browser (1), process_registry (2), image_gen (1)
- plugins/memory/: honcho (9), supermemory (9), hindsight (8),
  holographic (7), openviking (7), mem0 (7), byterover (6), retaindb (2)
- agent/: memory_manager (2), builtin_memory_provider (1)

plugins/memory/honcho/__init__.py

@@ -21,6 +21,7 @@ import threading
 from typing import Any, Dict, List, Optional
 
 from agent.memory_provider import MemoryProvider
+from tools.registry import tool_error
 
 logger = logging.getLogger(__name__)
 
@@ -638,15 +639,15 @@ class HonchoMemoryProvider(MemoryProvider):
     def handle_tool_call(self, tool_name: str, args: dict, **kwargs) -> str:
         """Handle a Honcho tool call, with lazy session init for tools-only mode."""
         if self._cron_skipped:
-            return json.dumps({"error": "Honcho is not active (cron context)."})
+            return tool_error("Honcho is not active (cron context).")
 
         # Port #1957: ensure session is initialized for tools-only mode
         if not self._session_initialized:
             if not self._ensure_session():
-                return json.dumps({"error": "Honcho session could not be initialized."})
+                return tool_error("Honcho session could not be initialized.")
 
         if not self._manager or not self._session_key:
-            return json.dumps({"error": "Honcho is not active for this session."})
+            return tool_error("Honcho is not active for this session.")
 
         try:
             if tool_name == "honcho_profile":
@@ -658,7 +659,7 @@ class HonchoMemoryProvider(MemoryProvider):
             elif tool_name == "honcho_search":
                 query = args.get("query", "")
                 if not query:
-                    return json.dumps({"error": "Missing required parameter: query"})
+                    return tool_error("Missing required parameter: query")
                 max_tokens = min(int(args.get("max_tokens", 800)), 2000)
                 result = self._manager.search_context(
                     self._session_key, query, max_tokens=max_tokens
@@ -670,7 +671,7 @@ class HonchoMemoryProvider(MemoryProvider):
             elif tool_name == "honcho_context":
                 query = args.get("query", "")
                 if not query:
-                    return json.dumps({"error": "Missing required parameter: query"})
+                    return tool_error("Missing required parameter: query")
                 peer = args.get("peer", "user")
                 result = self._manager.dialectic_query(
                     self._session_key, query, peer=peer
@@ -680,17 +681,17 @@ class HonchoMemoryProvider(MemoryProvider):
             elif tool_name == "honcho_conclude":
                 conclusion = args.get("conclusion", "")
                 if not conclusion:
-                    return json.dumps({"error": "Missing required parameter: conclusion"})
+                    return tool_error("Missing required parameter: conclusion")
                 ok = self._manager.create_conclusion(self._session_key, conclusion)
                 if ok:
                     return json.dumps({"result": f"Conclusion saved: {conclusion}"})
-                return json.dumps({"error": "Failed to save conclusion."})
+                return tool_error("Failed to save conclusion.")
 
-            return json.dumps({"error": f"Unknown tool: {tool_name}"})
+            return tool_error(f"Unknown tool: {tool_name}")
 
         except Exception as e:
             logger.error("Honcho tool %s failed: %s", tool_name, e)
-            return json.dumps({"error": f"Honcho {tool_name} failed: {e}"})
+            return tool_error(f"Honcho {tool_name} failed: {e}")
 
     def shutdown(self) -> None:
         for t in (self._prefetch_thread, self._sync_thread):