file: append "target" for symbolic links

file: append "target" for symbolic links

When list encounters a symbolic link, we add its nested "target" entry, to where
the symbolic link points. Just how `ls -l` reports.

So when calling e.g.: ubus call file list '{"path":"/etc"}'

instead of:

	...
	"name": "os-release",
	"type": "symlink",
	"size": 21,
	"mode": 41471,
	"atime": 1760891865,
	"mtime": 1760891865,
	"ctime": 1760891865,
	"inode": 266,
	"uid": 0,
	"gid": 0,
	"target_type": "file"
	...

We get:

	...
	"name": "os-release",
	"type": "symlink",
	"size": 21,
	"mode": 41471,
	"atime": 1760891865,
	"mtime": 1760891865,
	"ctime": 1760891865,
	"inode": 266,
	"uid": 0,
	"gid": 0,
	"target": {
		"name": "../usr/lib/os-release",
		"type": "file",
		"size": 582,
		"mode": 33188,
		"atime": 1760891865,
		"mtime": 1760891865,
		"ctime": 1760891865,
		"inode": 1744,
		"uid": 0,
		"gid": 0
	}
	...

And should a link be broken:

	"name": "foo",
	"type": "symlink",
	"size": 8,
	"mode": 41471,
	"atime": 1762640365,
	"mtime": 1762640365,
	"ctime": 1762640365,
	"inode": 348,
	"uid": 0,
	"gid": 0,
	"target": {
		"name": "/tmp/foo",
		"type": "broken"
	}

Tested on: OpenWrt 24.10.4 r28959-29397011cc
Signed-off-by: Paul Donald <[email protected]>
Tested-by: Eric Fahlgren <[email protected]>
Link: https://github.com/openwrt/rpcd/pull/21
Signed-off-by: Robert Marko <[email protected]>