Route direct-stdout command output through internal/ui (closes #149)

version, info, remote info, config, and database delete wrote plain text
straight to stdout, so they were unstyled and ignored --quiet. Output now
falls in two buckets, both governed by internal/ui.

Status lines and confirmations (config init, config set, database
delete) go through the ui message methods: styled, and --quiet silences
them. The data a command exists to produce is written plain, since a
marker would corrupt a table or a parsed document: the version, info, and
remote info reports, the snapshot list table, config get values, and the
--json documents. --quiet silences the human reports and tables but never
the config get value or the --json documents, which a script depends on.
The database delete confirmation prompt is always shown; it is an
interactive exchange the operator must see.

The pure-cli commands reach internal/ui through a small commandUI helper
that builds a ui.Writer on the command's stdout in quiet mode when
--quiet is set. NewForTesting now supplies a UI writer so the quiet gate
is never nil. The README output-style section states the resulting rule.

Model: opus-4-8

internal/cli/database.go

@@ -48,7 +48,7 @@ storage destination on that run.
 
 Use --force to skip the confirmation prompt.`,
 		Args: cobra.NoArgs,
-		RunE: func(_ *cobra.Command, _ []string) error {
+		RunE: func(cmd *cobra.Command, _ []string) error {
 			// Resolve config path
 			configPath, err := ResolveConfigPath()
 			if err != nil {
@@ -62,26 +62,31 @@ Use --force to skip the confirmation prompt.`,
 			}
 
 			dbPath := cfg.IndexPath
+			out := commandUI(cmd)
 
 			// Check if database exists
 			_, err = os.Stat(dbPath)
 			if os.IsNotExist(err) {
-				_, _ = fmt.Fprintf(os.Stdout, "Database does not exist: %s\n", dbPath)
+				out.Infof("Local state database does not exist: %s.", dbPath)
 
 				return nil
 			}
 
-			// Confirm unless --force
+			// Confirm unless --force. The prompt and its immediate result
+			// are an interactive exchange the operator must see, so they go
+			// straight to stdout rather than through the UI and --quiet does
+			// not silence them.
 			if !force {
-				_, _ = fmt.Fprintf(os.Stdout,
+				w := cmd.OutOrStdout()
+				_, _ = fmt.Fprintf(w,
 					"This will delete the local state database at:\n  %s\n\n", dbPath)
-				_, _ = fmt.Fprint(os.Stdout, "Are you sure? Type 'yes' to confirm: ")
+				_, _ = fmt.Fprint(w, "Are you sure? Type 'yes' to confirm: ")
 
 				var confirm string
 
 				_, err = fmt.Scanln(&confirm)
 				if err != nil || confirm != "yes" {
-					_, _ = fmt.Fprintln(os.Stdout, "Aborted.")
+					_, _ = fmt.Fprintln(w, "Aborted.")
 
 					//nolint:nilerr // a failed/aborted confirmation is a clean abort
 					return nil
@@ -100,11 +105,7 @@ Use --force to skip the confirmation prompt.`,
 			_ = os.Remove(walPath) // Ignore errors - files may not exist
 			_ = os.Remove(shmPath)
 
-			rootFlags := GetRootFlags()
-			if !rootFlags.Quiet {
-				_, _ = fmt.Fprintf(os.Stdout, "Database deleted: %s\n", dbPath)
-			}
-
+			out.Infof("Local state database deleted: %s.", dbPath)
 			log.Info("Local state database deleted", "path", dbPath)
 
 			return nil