feat: Enhance S3 migration CLI with new commands and EC2 detection option

src/deltaglider/app/cli/aws_compat.py

@@ -283,12 +283,14 @@ def copy_s3_to_s3(
                 tmp_path = Path(tmp.name)
 
                 # Write stream to temp file
-                with open(tmp_path, 'wb') as f:
+                with open(tmp_path, "wb") as f:
                     shutil.copyfileobj(source_stream, f)
 
             try:
                 # Use DeltaService.put() with override_name to preserve original filename
-                summary = service.put(tmp_path, dest_deltaspace, max_ratio, override_name=original_filename)
+                summary = service.put(
+                    tmp_path, dest_deltaspace, max_ratio, override_name=original_filename
+                )
 
                 if not quiet:
                     if summary.delta_size:
@@ -371,7 +373,9 @@ def migrate_s3_to_s3(
             click.echo(f"Migrating from s3://{source_bucket}/{source_prefix}")
             click.echo(f"           to s3://{dest_bucket}/{effective_dest_prefix}")
         else:
-            click.echo(f"Migrating from s3://{source_bucket}/{source_prefix} to s3://{dest_bucket}/{dest_prefix}")
+            click.echo(
+                f"Migrating from s3://{source_bucket}/{source_prefix} to s3://{dest_bucket}/{dest_prefix}"
+            )
         click.echo("Scanning source and destination buckets...")
 
     # List source objects
@@ -396,7 +400,9 @@ def migrate_s3_to_s3(
         source_objects.append(obj)
 
     # List destination objects to detect what needs copying
-    dest_list_prefix = f"{dest_bucket}/{effective_dest_prefix}" if effective_dest_prefix else dest_bucket
+    dest_list_prefix = (
+        f"{dest_bucket}/{effective_dest_prefix}" if effective_dest_prefix else dest_bucket
+    )
     dest_keys = set()
 
     for obj in service.storage.list(dest_list_prefix):
@@ -429,6 +435,7 @@ def migrate_s3_to_s3(
         return
 
     if not quiet:
+
         def format_bytes(size: int) -> str:
             size_float = float(size)
             for unit in ["B", "KB", "MB", "GB", "TB"]:
@@ -487,7 +494,7 @@ def migrate_s3_to_s3(
                 dest_s3_url,
                 quiet=True,
                 max_ratio=max_ratio,
-                no_delta=no_delta
+                no_delta=no_delta,
             )
 
             successful += 1
@@ -517,10 +524,13 @@ def migrate_s3_to_s3(
         if successful > 0 and not no_delta:
             try:
                 from ...client import DeltaGliderClient
+
                 client = DeltaGliderClient(service)
                 dest_stats = client.get_bucket_stats(dest_bucket, detailed_stats=False)
                 if dest_stats.delta_objects > 0:
-                    click.echo(f"\nCompression achieved: {dest_stats.average_compression_ratio:.1%}")
+                    click.echo(
+                        f"\nCompression achieved: {dest_stats.average_compression_ratio:.1%}"
+                    )
                     click.echo(f"Space saved: {format_bytes(dest_stats.space_saved)}")
             except Exception:
                 pass  # Ignore stats errors

src/deltaglider/app/cli/main.py

@@ -129,7 +129,14 @@ def _version_callback(ctx: click.Context, param: click.Parameter, value: bool) -
 
 @click.group()
 @click.option("--debug", is_flag=True, help="Enable debug logging")
-@click.option("--version", is_flag=True, is_eager=True, expose_value=False, callback=_version_callback, help="Show version and exit")
+@click.option(
+    "--version",
+    is_flag=True,
+    is_eager=True,
+    expose_value=False,
+    callback=_version_callback,
+    help="Show version and exit",
+)
 @click.pass_context
 def cli(ctx: click.Context, debug: bool) -> None:
     """DeltaGlider - Delta-aware S3 file storage wrapper."""
@@ -662,7 +669,9 @@ def verify(service: DeltaService, s3_url: str) -> None:
 @click.option("--max-ratio", type=float, help="Max delta/file ratio (default: 0.5)")
 @click.option("--dry-run", is_flag=True, help="Show what would be migrated without migrating")
 @click.option("--yes", "-y", is_flag=True, help="Skip confirmation prompt")
-@click.option("--no-preserve-prefix", is_flag=True, help="Don't preserve source prefix in destination")
+@click.option(
+    "--no-preserve-prefix", is_flag=True, help="Don't preserve source prefix in destination"
+)
 @click.option("--endpoint-url", help="Override S3 endpoint URL")
 @click.option("--region", help="AWS region")
 @click.option("--profile", help="AWS profile to use")