fix: clap CLI definitions and manpage generation

- add #[group(skip)] to all Parser-derived structs
- fix conflicts_with and arg definitions for correct CLI behavior
- refactor bin entry points to support manpage generation

core/man/start-cli/start-cli-backup-target-mount.1

@@ -0,0 +1,25 @@
+.ie \n(.g .ds Aq \(aq
+.el .ds Aq '
+.TH start-cli-backup-target-mount 1  "mount " 
+.SH NAME
+start\-cli\-backup\-target\-mount \- Mount a backup target
+.SH SYNOPSIS
+\fBstart\-cli backup target mount\fR [\fB\-\-server\-id\fR] [\fB\-\-allow\-partial\fR] [\fB\-h\fR|\fB\-\-help\fR] <\fITARGET_ID\fR> <\fIPASSWORD\fR> 
+.SH DESCRIPTION
+Mount a backup target
+.SH OPTIONS
+.TP
+\fB\-\-server\-id\fR \fI<SERVER_ID>\fR
+Unique server identifier
+.TP
+\fB\-\-allow\-partial\fR
+Leave media mounted even if backupfs fails to mount
+.TP
+\fB\-h\fR, \fB\-\-help\fR
+Print help
+.TP
+<\fITARGET_ID\fR>
+Backup target identifier
+.TP
+<\fIPASSWORD\fR>
+Password for backup encryption