test(settings): assert migrated settings display canonical path

Extend the #2730 settings migration harvest with the missing platform-config fallback display assertion from review, and keep the v0.9 execution map/changelog credit current.

Validation: cargo fmt --all -- --check; git diff --check; cargo test -p codewhale-tui --bin codewhale-tui --locked settings_ -- --nocapture; cargo test -p codewhale-tui --bin codewhale-tui --locked display_localizes_header_and_config_file_label -- --nocapture.

Harvested from PR #2730 by @xyuai.

Co-authored-by: xyuai <281015099+xyuai@users.noreply.github.com>

CHANGELOG.md

@@ -22,6 +22,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- `/config` now reports the canonical `~/.codewhale/settings.toml` path for TUI
+  settings while still reading legacy DeepSeek-branded settings fallbacks and
+  migrating them into the CodeWhale home on load.
 - Split `web_run` session/page cache state so cached page reads use shared
   page handles and do not serialize through the mutation path. The harvest also
   adds panic-safe state write-back and serializes cache-mutating unit tests so
@@ -47,7 +50,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 Thanks to **@cyq1017** for the restore-listing implementation (#2513) and
 **@wywsoor** for the broader macOS/iTerm rollback UX report (#2494), and
 **@HUQIANTAO** for the `web_run` lock-splitting work (#2502) and turn-metadata
-prefix-cache stability work (#2517), and **@shenjackyuanjie** for the
+prefix-cache stability work (#2517), **@xyuai** for canonical CodeWhale
+settings-path migration work (#2730), and **@shenjackyuanjie** for the
 HarmonyOS/OpenHarmony port and MatePad Edge validation trail (#2634).
 
 ## [0.8.53] - 2026-06-03