feat(files): Add deployment content push

[nfebe]

Push a local directory to a deployment in one request, with optional destination cleanup.

[sourceant]

Code Review Summary

This PR adds the capability to push a local directory to a deployment in a single request. It includes updates to the CLI command structure, the underlying API client, and comprehensive tests.

🚀 Key Improvements

• Introduced streaming directory uploads using io.Pipe, which scales well with large file sets.
• Added safety checks to block symbolic links during the archival process.
• Updated the generated command catalogue to support new file-related operations.
• Refactored the Client request logic to expose a reusable doRequest method.

💡 Minor Suggestions

• Centralize the Authorization header logic within the Client struct to avoid manual header management in specialized request methods like PushDeploymentFiles.

[sourceant]

Review complete. See the overview comment for a summary.

[sourceant]

Optimization: You can check if the entry is a symbolic link using entry.Type() before calling entry.Info(). Since entry.Type() is typically available directly from the directory traversal (e.g., via getdents on Linux), this can avoid an unnecessary stat syscall for every file in the directory tree, significantly improving performance for large source directories.

Suggested change

	info, err := entry.Info()
	+ if entry.Type()&os.ModeSymlink != 0 {
	+ return fmt.Errorf("symbolic links are not supported: %s", path)
	+ }
	+ info, err := entry.Info()
	+ if err != nil {
	+ return err
	+ }

[sourceant]

Review complete. See the overview comment for a summary.

[sourceant]

The Authorization header setting is duplicated here and in the main request logic (as seen in internal/flatrun/client.go). To ensure consistency and simplify future changes (e.g., changing auth schemes), consider extracting this into a private helper method on the Client struct.

Suggested change

	if c.token != "" {
	c.setAuthHeader(req)