docs(changelog): meet the dated-release contract before tagging

Moving the heading off "Unreleased candidate" flips
web/lib/public-surface-contract.test.ts onto its released branch, which requires
three things the candidate shape did not have:

- the intro names the version ("Codewhale v0.10.0 …", as 0.9.13's does),
- a [0.10.0]: compare link that ends ...v0.10.0 rather than ...HEAD,
- and [Unreleased] moving up to compare/v0.10.0...HEAD.

Both the release candidate and Web Frontend failed on exactly this:
AssertionError: expected '# Changelog\n\nAll notable changes to…' to contain
'Codewhale v0.10.0'.

The candidate shape hid it: while the heading said "Unreleased candidate" the
same test asserted `v0.10.0 source candidate` instead, so the dated-release
requirements only bite at the moment of release.

Evidence: npx vitest run (web) -> 51 files, 471 passed, 0 failed;
prepare-release.sh 0.10.0 -> version state OK, OHOS contracts OK; compare links
regenerated into crates/tui/CHANGELOG.md and web/lib/changelog.generated.ts.

CHANGELOG.md

@@ -9,10 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [0.10.0] - 2026-09-22
 
-The v0.10.0 source candidate brings a redesigned terminal workbench, clearer
-settings, and more reliable session and runtime behavior. It supersedes the
-unpublished v0.9.14 candidate. Nothing below is published until the matching
-tag, packages, checksums and release assets exist.
+Codewhale v0.10.0 brings a redesigned terminal workbench, clearer settings, and
+more reliable session and runtime behavior. It supersedes the unpublished
+v0.9.14 candidate.
 
 ### Contributors
 
@@ -9311,8 +9310,8 @@ overflow report and `/theme` picker edge-wrapping patch in #1814.
 
 Older releases (v0.8.39 and earlier) are archived in [docs/CHANGELOG_ARCHIVE.md](docs/CHANGELOG_ARCHIVE.md).
 
-[Unreleased]: https://github.com/Hmbown/CodeWhale/compare/v0.9.13...HEAD
-[0.10.0]: https://github.com/Hmbown/CodeWhale/compare/v0.9.13...HEAD
+[Unreleased]: https://github.com/Hmbown/CodeWhale/compare/v0.10.0...HEAD
+[0.10.0]: https://github.com/Hmbown/CodeWhale/compare/v0.9.13...v0.10.0
 [0.9.13]: https://github.com/Hmbown/CodeWhale/compare/v0.9.12...v0.9.13
 [0.9.12]: https://github.com/Hmbown/CodeWhale/compare/v0.9.11...v0.9.12
 [0.9.11]: https://github.com/Hmbown/CodeWhale/compare/v0.9.10...v0.9.11

crates/tui/CHANGELOG.md

@@ -9,10 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [0.10.0] - 2026-09-22
 
-The v0.10.0 source candidate brings a redesigned terminal workbench, clearer
-settings, and more reliable session and runtime behavior. It supersedes the
-unpublished v0.9.14 candidate. Nothing below is published until the matching
-tag, packages, checksums and release assets exist.
+Codewhale v0.10.0 brings a redesigned terminal workbench, clearer settings, and
+more reliable session and runtime behavior. It supersedes the unpublished
+v0.9.14 candidate.
 
 ### Contributors
 

web/lib/changelog.generated.ts

@@ -25,14 +25,14 @@ export const CHANGELOG: ChangelogRelease[] = [
     "version": "Unreleased",
     "date": null,
     "unreleased": true,
-    "compareUrl": "https://github.com/Hmbown/CodeWhale/compare/v0.9.13...HEAD",
+    "compareUrl": "https://github.com/Hmbown/CodeWhale/compare/v0.10.0...HEAD",
     "sections": []
   },
   {
     "version": "0.10.0",
     "date": "2026-09-22",
     "unreleased": false,
-    "compareUrl": "https://github.com/Hmbown/CodeWhale/compare/v0.9.13...HEAD",
+    "compareUrl": "https://github.com/Hmbown/CodeWhale/compare/v0.9.13...v0.10.0",
     "sections": [
       {
         "heading": "Contributors",