fix: extract exFAT OPTION containers that contain empty files

exfat-fs 0.1.3's StreamExtensionEntry::valid() rejects any entry with
FirstCluster < 2, but a zero-length file (or empty dir) legitimately has
FirstCluster = 0 / DataLength = 0 per the exFAT spec. The parser returned
InvalidStreamExtension and aborted the *entire* directory tree the moment it
hit one empty file, so real OPTION (.opt) containers failed to extract with:

    WARNING: Failed to extract exfat contents: InvalidFileEntry(InvalidStreamExtension)

even though unsega/7-Zip read them fine.

0.1.3 is the latest published release and its `main` has an incompatible
public API, so override the dependency via [patch.crates-io] with a fork
branch that is the 0.1.3 release plus only the one-function fix (gate the
cluster check on DataLength: 0 -> FirstCluster must be 0, else >= 2).

Regenerate the synthetic OPTION fixture with a zero-byte file so tests/e2e.rs
reproduces the bug: without the patch it fails with InvalidStreamExtension;
with it, extraction succeeds. Verified against a real 191 MB OPTION container
(1602 files / 1217 dirs, empty file written as 0 bytes) and the full suite.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Cargo.lock

@@ -481,8 +481,7 @@ dependencies = [
 [[package]]
 name = "exfat-fs"
 version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5cbdfa8ecf36ab2341032974d3644a56f1e40c9da3b643118492cf97f357f3c5"
+source = "git+https://github.com/jujuforce/exfat-fs.git?rev=7067f6afe3c21d9c737288475b29e5dae790e206#7067f6afe3c21d9c737288475b29e5dae790e206"
 dependencies = [
  "bitflags",
  "bytemuck",

Cargo.toml

@@ -21,3 +21,13 @@ cipher = { version = "0.4.4", features = ["alloc"] }
 lto = "thin"
 codegen-units = 1
 strip = "none"
+
+# exfat-fs 0.1.3 rejects empty (zero-length) files/dirs: its
+# StreamExtensionEntry::valid() treats FirstCluster < 2 as invalid, but an
+# empty file legitimately has FirstCluster = 0 / DataLength = 0. That aborts
+# the whole extraction the moment an OPTION container contains any 0-byte file.
+# Until the fix lands in a published release, override with a fork branch that
+# is the 0.1.3 release plus only that one-function fix (identical public API).
+# See https://github.com/jujuforce/exfat-fs/tree/v0.1.3-empty-file-fix
+[patch.crates-io]
+exfat-fs = { git = "https://github.com/jujuforce/exfat-fs.git", rev = "7067f6afe3c21d9c737288475b29e5dae790e206" }