fix(daemon): allow read-only daemon commands with Dolt backend

The daemon guard was blocking ALL daemon commands when using Dolt
backend, including read-only commands like `status`, `stop`, `logs`.

Changes:
- Rename guard to `guardDaemonStartForDolt` (more accurate)
- Remove `PersistentPreRunE` from `daemonCmd` and `daemonsCmd`
- Add `PreRunE` guard only to `daemonStartCmd` and `daemonsRestartCmd`
- Update test to use new function name and test start command

Now:
- `bd daemon status` works with Dolt backend
- `bd daemon start` blocked unless `--federation` flag
- `bd daemon start --federation` works (starts dolt sql-server)

Fixes: bd-n7o47

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

cmd/bd/daemon.go

@@ -48,7 +48,6 @@ Common operations:
   bd daemon killall              Stop all running daemons
 
 Run 'bd daemon --help' to see all subcommands.`,
-	PersistentPreRunE: guardDaemonUnsupportedForDolt,
 	Run: func(cmd *cobra.Command, args []string) {
 		start, _ := cmd.Flags().GetBool("start")
 		stop, _ := cmd.Flags().GetBool("stop")