release v0.9.7: kernel_range drift fix + CI Node 24 readiness

Tags the maintenance work landed since v0.9.6. The fragnesia drift fix (35c33df) and checkout v4->v6 bump (6c148e2) are already on main; this commit adds the remaining CI Node-24 bumps + version strings.

release.yml: upload-artifact v4->v7, download-artifact v4->v8, softprops/action-gh-release v2->v3 (last of the Node-20-era actions; GitHub forces node24 on 2026-06-16). Reviewed each changelog — our default-zip/unique-name upload + full-set download is unaffected by the major-version breaking changes (opt-in direct uploads, download-by-ID path).

Version bumped to 0.9.7 (skeletonkey.c, README, docs/index.html) + v0.9.7 RELEASE_NOTES entry. Tagging this commit fires release.yml — the end-to-end test of the new artifact actions, incl. the Alpine/musl static job under node24.

docs/index.html

@@ -56,7 +56,7 @@
   <div class="container hero-inner">
     <div class="hero-eyebrow">
       <span class="dot dot-pulse"></span>
-      v0.9.6 — released 2026-05-28
+      v0.9.7 — released 2026-06-01
     </div>
     <h1 class="hero-title">
       <span class="display-wordmark">SKELETONKEY</span>
@@ -598,7 +598,7 @@ uid=0(root) gid=0(root)</pre>
       who found the bugs.
     </p>
     <p class="footer-meta">
-      v0.9.6 · MIT · <a href="https://github.com/KaraZajac/SKELETONKEY">github.com/KaraZajac/SKELETONKEY</a>
+      v0.9.7 · MIT · <a href="https://github.com/KaraZajac/SKELETONKEY">github.com/KaraZajac/SKELETONKEY</a>
     </p>
   </div>
 </footer>