* Documentation for autodiff.

* Fix remarks and build errors.

* Trying to fix msvc.

* Update results for regression tests.

* Make AD warning be not an error so regression tests run

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Co-authored-by: Herb Sutter <herb.sutter@gmail.com>

And update dates to 2026

* Add runtime check for modulo by zero

* Rerun regression tests

One of the tests now hits an MSVC error I've seen before, related to using std::source_location via module std import -- it doesn't manifest on any other compiler, or in MSVC using std headers. So the error is spurious, but I'm not able to debug it or find a workaround, and I don't want to record regression test failures just because of that use case where 'module std currently doesn't work.' So this commit also changes all -pure regression tests to use headers, not modules, at least for now until modules work better

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Co-authored-by: Herb Sutter <herb.sutter@gmail.com>

* CI Update runners in the build-cppfront.yaml

* CI Update runners in the regression-tests.yml

* CI Use -include-std cppfront option for pure regression tests

Including regression test cases

TODO: write docs

Basic usage is

    try {
        ...
    }
    catch( i: int ) { use(i); } // catch an int
    catch( _ ) { } // catch everything

And bump build number

And 'encapsulated' and 'noncopyable' metaclasses

Signed-off-by: Herb Sutter <herb.sutter@gmail.com>