chore: use image default features (rayon already in dep tree)

rayon is already pulled in by candle-core, docx-rs, and others,
so no reason to exclude it from image.

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

Author: jh-block

Cargo.lock

@@ -46,7 +46,7 @@ once_cell = { workspace = true }
 ignore = { workspace = true }
 lopdf = "0.36.0"
 docx-rs = "0.4.7"
-image = { version = "0.25", default-features = false, features = ["default-formats"] }
+image = "0.25"
 umya-spreadsheet = "2.2.3"
 which = {workspace = true}
 lru = { workspace = true }