Add logs tab with real-time server output and consolidate syntax highlighting

- Implement dedicated Logs tab showing stdout/stderr from OpenCode server
- Add log level parsing (INFO, ERROR, WARN, DEBUG) with color coding
- Stream logs from main process to renderer via IPC events
- Persist scroll position and auto-scroll state per instance
- Synchronize instance IDs between renderer and main process
- Consolidate syntax highlighting to single shared highlighter instance
- Optimize markdown rendering with global highlighter initialization
- Fix code block copy button to always appear on right side
- Enable debug logging with --print-logs --log-level DEBUG flags

src/index.css

@@ -948,6 +948,7 @@ body {
   cursor: pointer;
   color: #666;
   transition: all 150ms ease;
+  margin-left: auto;
 }
 
 [data-theme="dark"] .code-block-copy {