Unreleased changelog fragments that no longer describe the release #8971

Found by differential semantic drift analysis from a7721303 to b123b7c3.

What is broken

Several unreleased changelog fragments no longer describe what the next release contains. yarn changelog:release would publish them as written.

• changes/semantic-diff-fragments.internal.md (Read the semantic diff's changelog from changes/ fragments #8881) says the semantic diff page reads its changelog from changes/ fragments. Semantic diff: write and draw changes as semantic objects #8908 removed that reading (fragmentsOf); scripts/commitRecords.js and scripts/recordRender.js no longer read fragments.
• changes/linear-char-range-patterns.fix.md (Compile character range patterns in linear time #8868) promises to "speed up switches over many constants". Remove the hashing fast paths from pattern matching #8900 removed those hashing fast paths (matching.ml L1171 is a plain walk; its commit message measures 10,000 int cases at 3.23 s before and 6.27 s after), and its own fragment changes/remove-match-fast-paths.internal.md says the opposite.
• changes/playground-api-v8-compatibility.fix.md (Keep optimized Lambda output compatible with playground API v8 #8930) announces a fix that keeps playground API v8; the bump to v9 it reverts (Developer playground: compare Lambda before and after optimization #8636) is in the same unreleased cycle, so no release had the regression.
• changes/watch-rebuild-recovery.fix.md (Keep watch alive after rebuild errors #8641) promises to "retry initialization on source edits". Keep watch alive after rebuild errors #8641 changed only the Rust watcher; rewatch-ocaml/README.md L107-L108 says the OCaml watcher, which rescript runs, recovers only on configuration changes. Likewise changes/rewatch-overlapping-unwatch.fix.md (Fix rewatch losing watches when an overlapping source folder is removed #8839, Rust-only) says "Rewatch:", which no longer names one binary.
• changes/ocaml-rewatch-strict-config.breaking.md names three new rejections, while rewatch-ocaml/README.md L86-L115 lists further user-visible differences that no fragment mentions: --filter rejects constructs such as (?i), a failing --after-build fails the build and hooks get no interactive terminal, format -v and compiler-args -v log to stderr, and OpenTelemetry export is not implemented.

Possible cause (speculation only)

A guess: each pull request adds its own fragment, and nothing prompts a later pull request to revisit the unreleased fragments it supersedes or contradicts.