feature: add file operation tools (list, read, write, search, find)

[hjpinheiro]

Summary

The plugin currently only supports uploading files from Dify and downloading files to Dify. These 5 new tools cover the fundamental file operations needed for working with files inside a sandbox:

Tool	Purpose	SDK API
list_files	List directory contents (name, size, type, permissions)	sandbox.fs.list_files(path)
read_file	Read text file content as UTF-8	sandbox.fs.download_file(path)
write_file	Create or overwrite a text file	sandbox.fs.upload_file(data, path)
search_files	Find files by glob pattern (like find -name)	sandbox.fs.search_files(path, pattern)
find_in_files	Search file contents by pattern (like grep -r)	sandbox.fs.find_files(path, pattern)

Design

All tools follow the existing convention of upload_file and download_file:

• sandbox_id is required (explicit, no magic discovery)
• Minimal error handling — SDK exceptions propagate naturally
• Each tool yields create_json_message with structured results
• read_file and list_files also yield create_text_message for human-readable output

New parameters in YAML

Each tool has 2-3 parameters (following the upstream's minimal style):

• list_files: sandbox_id, path
• read_file: sandbox_id, remote_path
• write_file: sandbox_id, remote_path, content
• search_files: sandbox_id, path, pattern
• find_in_files: sandbox_id, path, pattern

Files

• 10 new files: tools/{list_files,read_file,write_file,search_files,find_in_files}.{py,yaml}
• 1 modified: provider/daytona.yaml (5 new tool registrations)

Testing

• All 5 .py files pass py_compile
• All 5 .yaml files pass yaml.safe_load
• provider/daytona.yaml validates with 12 total tools (7 original + 5 new)