unbundle: extend object verification for fetches

The existing fetch.fsckObjects and transfer.fsckObjects configurations
were not fully applied to bundle-involved fetches, including direct
bundle fetches and bundle-uri enabled fetches. Furthermore, there was no
object verification support for unbundle.

This commit extends object verification support in `bundle.c:unbundle`
by adding the `VERIFY_BUNDLE_FSCK` option to `verify_bundle_flags`. When
this option is enabled, we append the `--fsck-objects` flag to
`git-index-pack`.

The `VERIFY_BUNDLE_FSCK` option is now used by bundle-involved fetches,
where we use `fetch-pack.c:fetch_pack_fsck_objects` to determine whether
to enable this option for `bundle.c:unbundle`, specifically in:

- `transport.c:fetch_refs_from_bundle` for direct bundle fetches.
- `bundle-uri.c:unbundle_from_file` for bundle-uri enabled fetches.

This addition ensures a consistent logic for object verification during
fetches. Tests have been added to confirm functionality in the scenarios
mentioned above.

Reviewed-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Xing Xin <xingxin.xx@bytedance.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

bundle-uri.c

@@ -9,6 +9,7 @@
 #include "hashmap.h"
 #include "pkt-line.h"
 #include "config.h"
+#include "fetch-pack.h"
 #include "remote.h"
 
 static struct {
@@ -373,7 +374,7 @@ static int unbundle_from_file(struct repository *r, const char *file)
 	 * the prerequisite commits.
 	 */
 	if ((result = unbundle(r, &header, bundle_fd, NULL,
-			       VERIFY_BUNDLE_QUIET)))
+			       VERIFY_BUNDLE_QUIET | (fetch_pack_fsck_objects() ? VERIFY_BUNDLE_FSCK : 0))))
 		return 1;
 
 	/*