Merge nucleic/sleek-thistle-egret-fyej into dev

corpus/DIVERGENCES.md

@@ -27,3 +27,11 @@ stays open until fixed in the fork (or upstream) and re-verified by the corpus.
   `expansion.rs`). Corpus back to 100% (94/94); candidate for upstreaming.
 - **Regression tests**: corpus `ifs-split` (+ `glob-all`, `glob-txt`,
   `cond-pattern`, `case` guard the glob/pattern side); brush compat suite.
+- **Fix fallout (caught by the brush compat suite, both fixed)**: (a) text
+  substituted by `${v:-word}`/`${v:+word}`/`${v:=word}` *is* an expansion result
+  and must split — restored via a boundary conversion in the
+  `ParameterExpansion` arm; (b) `compgen -W` splits its word-list string as
+  data — restored via `ExpanderOptions.field_split_literal_text`. Final suite:
+  1684 succeeded / 6 failed, failure set identical to the pristine-brush
+  baseline in this container (environmental only); 3 upstream known-fail IFS
+  tests now pass (markers flipped in `ifs.yaml`).