Gather every model under one tree at the repository root

The weights were in two places: face detection and recognition in
`models/face/`, segmentation in `core/dr-segment/models/`. Nothing was
wrong with either path, but between them there was nowhere to look to
answer "how much model does this application carry", and that number is
about to start growing.

So the crate-local copy moves up beside the other. `models/` now holds
`face/` and `segment/`, and a `du -sh` of one directory is the whole
answer.

No content changes: the .onnx and its vocabulary are byte-identical, and
`LICENCE.md` moves up a level to cover the tree rather than one crate.
The LFS pattern in `.gitattributes` is `*.onnx` and already matched both
locations, so only its comment needed the new path.

`include_bytes!` is relative to the source file and `build.rs` runs with
the crate root as its working directory, which is why the two paths climb
a different number of levels.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

core/dr-segment/src/semantic.rs

@@ -20,7 +20,7 @@
 //!   behaviour, and it is worth being glad of rather than working around.
 //!
 //! So arm B here contributes *subjects*, and the watershed contributes
-//! everything else. See `models/LICENCE.md` for why no ADE20K variant is
+//! everything else. See `models/LICENCE.md` at the repository root for why no ADE20K variant is
 //! shipped instead.
 //!
 //! # Cost, and where it may run
@@ -198,15 +198,15 @@ pub struct SemanticModel {
     classes: Vec<Arc<str>>,
 }
 
-/// The weights that ship with this crate (`models/`, AGPL — see LICENCE.md).
+/// The weights, from the repository-root `models/segment/` (AGPL — see `models/LICENCE.md`).
 ///
 /// Embedded rather than read from a path because Android hands the app no
 /// filesystem location to read from (ARCH §6.9) — the same reasoning that has
 /// the Lensfun database shipping inside its crate.
 #[cfg(feature = "embedded-model")]
-const EMBEDDED_MODEL: &[u8] = include_bytes!("../models/yolo26n-seg.onnx");
+const EMBEDDED_MODEL: &[u8] = include_bytes!("../../../models/segment/yolo26n-seg.onnx");
 #[cfg(feature = "embedded-model")]
-const EMBEDDED_CLASSES: &str = include_str!("../models/yolo26n-seg.classes.json");
+const EMBEDDED_CLASSES: &str = include_str!("../../../models/segment/yolo26n-seg.classes.json");
 
 impl SemanticModel {
     /// Load the model that ships with this crate.