Remove manual migrate command

Migration now happens automatically when the database schema is
updated (in Library._make_table()), so the manual 'beet migrate'
command is no longer needed.

Addresses PR review comment.

beets/ui/commands/__init__.py

@@ -24,7 +24,6 @@ from .fields import fields_cmd
 from .help import HelpCommand
 from .import_ import import_cmd
 from .list import list_cmd
-from .migrate import migrate_cmd
 from .modify import modify_cmd
 from .move import move_cmd
 from .remove import remove_cmd
@@ -53,13 +52,12 @@ default_commands = [
     HelpCommand(),
     import_cmd,
     list_cmd,
-    migrate_cmd,
-    modify_cmd,
-    move_cmd,
+    update_cmd,
     remove_cmd,
     stats_cmd,
-    update_cmd,
     version_cmd,
+    modify_cmd,
+    move_cmd,
     write_cmd,
     config_cmd,
     completion_cmd,

beets/ui/commands/migrate.py

@@ -1,98 +0,0 @@
-"""The 'migrate' command: migrate library data for format changes."""
-
-from beets import logging, ui
-from beets.autotag import correct_list_fields
-
-# Global logger.
-log = logging.getLogger("beets")
-
-
-def migrate_genres(lib, pretend=False):
-    """Migrate comma-separated genre strings to genres list.
-
-    For users upgrading from previous versions, their genre field may
-    contain comma-separated values (e.g., "Rock, Alternative, Indie").
-    This command splits those values into the genres list, avoiding
-    the need to reimport the entire library.
-    """
-    items = lib.items()
-    migrated_count = 0
-    total_items = 0
-
-    ui.print_("Scanning library for items with comma-separated genres...")
-
-    for item in items:
-        total_items += 1
-        genre_val = item.genre or ""
-        genres_val = item.genres or []
-
-        # Check if migration is needed
-        needs_migration = False
-        if not genres_val and genre_val:
-            for separator in [", ", "; ", " / "]:
-                if separator in genre_val:
-                    split_genres = [
-                        g.strip()
-                        for g in genre_val.split(separator)
-                        if g.strip()
-                    ]
-                    if len(split_genres) > 1:
-                        needs_migration = True
-                        break
-
-        if needs_migration:
-            migrated_count += 1
-            old_genre = item.genre
-            old_genres = item.genres or []
-
-            if pretend:
-                # Just show what would change
-                ui.print_(
-                    f"  Would migrate: {item.artist} - {item.title}\n"
-                    f"    genre: {old_genre!r} -> {split_genres[0]!r}\n"
-                    f"    genres: {old_genres!r} -> {split_genres!r}"
-                )
-            else:
-                # Actually migrate
-                correct_list_fields(item)
-                item.store()
-                log.debug(
-                    "migrated: {} - {} ({} -> {})",
-                    item.artist,
-                    item.title,
-                    old_genre,
-                    item.genres,
-                )
-
-    # Show summary
-    if pretend:
-        ui.print_(
-            f"\nWould migrate {migrated_count} of {total_items} items "
-            f"(run without --pretend to apply changes)"
-        )
-    else:
-        ui.print_(
-            f"\nMigrated {migrated_count} of {total_items} items with "
-            f"comma-separated genres"
-        )
-
-
-def migrate_func(lib, opts, args):
-    """Handle the migrate command."""
-    if not args or args[0] == "genres":
-        migrate_genres(lib, pretend=opts.pretend)
-    else:
-        raise ui.UserError(f"unknown migration target: {args[0]}")
-
-
-migrate_cmd = ui.Subcommand(
-    "migrate", help="migrate library data for format changes"
-)
-migrate_cmd.parser.add_option(
-    "-p",
-    "--pretend",
-    action="store_true",
-    help="show what would be changed without applying",
-)
-migrate_cmd.parser.usage = "%prog migrate genres [options]"
-migrate_cmd.func = migrate_func