Document the new tools in the prompt and read-only variants

The tool guidance covers apply_patch and web_fetch, the approval line derives from the tools actually offered rather than a hardcoded edit-tool check, and plan and review gain approved web research when the net set is on.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/agents.ts

@@ -38,6 +38,7 @@ const READ_ONLY = [
   'git_show',
   'git_blame',
   'task',
+  'web_fetch',
   'todo_write',
   'remember',
   'recall',