Trim PR 8580 changelog entry

Author: cristianoc

CHANGELOG.md

@@ -52,7 +52,7 @@
 #### :house: Internal
 
 - Give nominal variants one canonical runtime layout: compute their JavaScript representation once after typing each declaration, replace positional constructor tags with semantic runtime descriptors, and make construction, matching, coercion, printing, diagnostics, and GenType consume the stored representation instead of reinterpreting annotations. Pattern matching keeps occurrence-specific plans local without adding another Lambda or Lam expression form. https://github.com/rescript-lang/rescript/pull/8579
-- Represent optional parameters with defaults structurally instead of recovering them downstream by pattern-matching on the synthetic `*opt_<label>*`/`*sth*` variable names: `Typedtree.function_param` gains an `fp_has_default` field, the type checker gives the compiled parameter its final `<label>Opt` ident before the typedtree leaves the function, and the name-sniffing consumers (`lam_convert`'s shape-matching rename pass, `matching`'s `*sth*` peephole, gentype's prefix check, and typecore's dead `is_fake_let`/`#default` vestiges) are deleted or generalized. Parameter names in emitted JS now consistently derive from the label, including cases the old shape-match silently missed and leaked mangled names for (`$staropt_id$star` → `idOpt`), and an unused defaulted parameter warns as an unused parameter (27) rather than an unused let binding (26). The CMT magic number is bumped to `Caml1999T025`. https://github.com/rescript-lang/rescript/pull/8580
+- Represent optional parameters with defaults structurally, removing downstream name-based detection and producing more consistent JavaScript parameter names. https://github.com/rescript-lang/rescript/pull/8580
 - Sync the platform npm package's compiler binaries (`packages/@rescript/<platform>/bin`) via dune promotion on every `dune build`, instead of Makefile/CI copy steps that only ran when make did: a plain `dune build` can no longer leave `cli/*.js` and the test harnesses running a stale compiler. https://github.com/rescript-lang/rescript/pull/8560
 - Remove unused compiler IR definitions, modules, helpers, error variants, and Typedtree fields. https://github.com/rescript-lang/rescript/pull/8551 https://github.com/rescript-lang/rescript/pull/8555
 - Make locally abstract value constraints (`let f: type a. t = value`) structural in the parsetree, remove the obsolete `Pexp_newtype` and `Texp_newtype` wrapper metadata, and keep the old encoding confined to the frozen external-PPX bridge. The CMT magic number is bumped to `Caml1999T024`. https://github.com/rescript-lang/rescript/pull/8575