Merge PR #1963: M12: Describe selections from SAM 3's semantic mask: sure inside, no lines between instances

docs/ai-masks.md

@@ -16,7 +16,10 @@ In the Masking panel (M):
   to leave it out. Clicks show as green (include) and red (leave out) dots.
 - **Describe**: type what to select — `sky`, `trees`, `the red car` — and press Return. Every
   instance the model finds (score above 0.5) joins the mask; if nothing matches, nothing is
-  created and you are told so.
+  created and you are told so. Around what it found, the mask follows the model's semantic mask
+  for the phrase, which is sure inside and runs on where two instances touch (the instances'
+  own masks alone left a sky or a net about 70–90 % selected and a thin line between two people
+  side by side).
 - Several things at once: `car, road` (comma-separated) selects each and merges them.
 - **+ / −** under the selected mask (and the Add / Subtract / Intersect menus) combine
   selections: Describe `car`, click the mask, + ▸ Describe… `road`; − ▸ Describe… `people` takes
@@ -214,7 +217,7 @@ wait and return the result (when built with the `sam` feature; the default CLI h
   `NOTICE` — the ported files say so and that they were modified): the 32-layer ViT backbone
   with 2-D RoPE and windowed attention, the feature pyramids, the SAM 2-style prompt encoder and
   two-way mask decoder for clicks, and the CLIP text encoder, DETR encoder/decoder (box
-  relative-position bias, presence token) and pixel decoder for text. The CLIP tokenizer is a
+  relative-position bias, presence token), pixel decoder and semantic head for text. The CLIP tokenizer is a
   small BPE in `tokenizer.rs`. The downloader (original code) is the `lightcraft-fetch` crate, shared by any model that is downloaded; `fetch/` here says what SAM 3 needs.
 - candle is pinned at 0.9.2: later releases make `candle-core` depend on `tokenizers` with the
   Oniguruma C library, and the product is pure Rust. Weights are read with positional reads (no