feat: support nested subdirectory navigation in /project command

[caiohamamura]

This pull request adds support for nested subdirectory navigation in the /project command.

Changes:

• Scans workspaces recursively and allows navigation through folders directly in the Telegram UI.
• Adds pagination support for deeply nested directories.
• Reuses the existing IDE window instead of launching a new window when switching project paths.
• Resolves workspace matches when the open workspace is a parent directory of the selected project.