test(skills): add bytes-vs-str equivalence and on-disk hash parity tests

Follow-up on #9925 cherry-pick adding two additional tests:
- bytes content hashes identically to its str-decoded form
- mixed bytes+str bundle hash equals the on-disk content_hash from
  skills_guard (the production invariant used to detect drift)

Also map dodofun@126.com and 1615063567@qq.com in AUTHOR_MAP so the
CI contributor check passes for the cherry-picked commit.

Co-authored-by: LeonSGP43 <cine.dreamer.one@gmail.com>
Co-authored-by: zhao0112 <1615063567@qq.com>

scripts/release.py

@@ -633,6 +633,8 @@ AUTHOR_MAP = {
     "cirwel@The-CIRWEL-Group.local": "CIRWEL",
     "molvikar8@gmail.com": "molvikar",
     "nftpoetrist@gmail.com": "nftpoetrist",
+    "dodofun@126.com": "colorcross",
+    "1615063567@qq.com": "zhao0112",
     "leozeli@qq.com": "leozeli",
     "linlehao@cuhk.edu.cn": "LehaoLin",
     "liutong@isacas.ac.cn": "I3eg1nner",