tweak: add newline between <content> and first line of read tool output to prevent confusion

[rekram1-node]

Ex:

This:

<content>1: <p align="center">
2:   <a href="https://opencode.ai">
3:     <picture>
4:       <source srcset="packages/console/app/src/asset/logo-ornate-dark.svg" media="(prefers-color-scheme: dark)">
</content>

Becomes this:

<content>
1: <p align="center">
2:   <a href="https://opencode.ai">
3:     <picture>
4:       <source srcset="packages/console/app/src/asset/logo-ornate-dark.svg" media="(prefers-color-scheme: dark)">
</content>