fix: remove unused imports and fix import sorting in clone modules

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: CosmoHac

src/roam/commands/cmd_clones.py

@@ -16,8 +16,6 @@
 from roam.commands.resolve import ensure_index
 from roam.db.connection import open_db
 from roam.output.formatter import (
-    abbrev_kind,
-    format_table,
     json_envelope,
     loc,
     to_json,

src/roam/graph/clone_detect.py

@@ -25,7 +25,6 @@
 from dataclasses import dataclass, field
 from pathlib import Path
 
-
 # Node types whose text values are normalized (treated as equivalent)
 _NORMALIZED_LEAF_TYPES = frozenset(
     {