fix(permissions): ensure omo permission overrides take precedence over opencode defaults

The spread order in applyToolConfig was incorrect - omo's external_directory: 'allow'
was placed BEFORE the config.permission spread, allowing opencode's default 'ask' to
overwrite it. This caused write/edit tools to hang on headless opencode serve sessions
(no TUI to approve permission prompts).

Move omo's permission overrides AFTER the base config spread so they always win.

Fixes write/edit tool hangs when running opencode serve headlessly.

src/plugin-handlers/tool-config-handler.ts

@@ -116,9 +116,9 @@ export function applyToolConfig(params: {
   }
 
   params.config.permission = {
+    ...(params.config.permission as Record<string, unknown>),
     webfetch: "allow",
     external_directory: "allow",
-    ...(params.config.permission as Record<string, unknown>),
     task: "deny",
   };
 }