Automatic toolchain upgrade to nightly-2025-11-26

[github-actions]

Update Rust toolchain from nightly-2025-11-25 to nightly-2025-11-26 without any other source changes.

[github-actions]

This is an automatically generated pull request. If any of the CI checks fail,
manual intervention is required. In such a case, review the changes at
https://github.com/rust-lang/rust from
rust-lang/rust@c871d09 up to
rust-lang/rust@80d8f29. The log
for this commit range is:

https://github.com/rust-lang/rust/commit/80d8f292d8 Auto merge of #149322 - matthiaskrgr:rollup-uf0hmx6, r=matthiaskrgr

rust-lang/rust@f40d8256eb Rollup merge of #149305 - tisonkun:oncecell-simplify, r=chenyukang
rust-lang/rust@ac7b0bd7a8 Rollup merge of #149302 - zjumathcode:main, r=jackh726
rust-lang/rust@d6966fa15a Rollup merge of #149274 - GuillaumeGomez:tyalias-method-link, r=lolbinarycat
rust-lang/rust@50237b33d6 Rollup merge of #149268 - davidtwco:v0-mangling-global-asm-namespace, r=Kivooeo
rust-lang/rust@2f566a88f4 Rollup merge of #149210 - ShoyuVanilla:issue-148161, r=jdonszelmann
rust-lang/rust@53276ad027 Rollup merge of #149167 - adwinwhite:next-245, r=lcnr
rust-lang/rust@7c96106cb0 Rollup merge of #148652 - rperier:report_no_match_method_error-refactoring, r=lcnr
rust-lang/rust@04e4f95e7e Rollup merge of #147736 - folkertdev:stabilize-asm-cfg, r=jdonszelmann
rust-lang/rust@0f6dae4afc Auto merge of #148122 - saethlin:deny-deref-nullptr, r=petrochenkov
rust-lang/rust@7934bbdf84 Auto merge of #149148 - davidtwco:v0-mangling-on-nightly-std, r=Kobzol
rust-lang/rust@a700e47675 Simplify OnceCell Clone impl
rust-lang/rust@d8c9d70508 Fix comment wording in simplify_comparison_integral.rs
rust-lang/rust@cdb4236e65 Auto merge of #149200 - yaahc:helper-compat-test, r=petrochenkov
rust-lang/rust@4752322343 Add a little cfg_attr(bootstrap) to make the doctest work on stage1
rust-lang/rust@bef49a02ef Don't lint on derefs of null pointers to ZSTs
rust-lang/rust@c0097978aa Make deref_nullptr deny by default instead of warn