Auto merge of #25572 - pshaughn:atomnames, r=jdm

Make name content attributes consistently atoms and put them in rare_data for fast access

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All codepaths setting the name content attribute now use an atom, which is also stored in rare_data for direct lookup by a get_name method.

Paralleling the get_name method, I added a get_id method, which makes some internal id-lookup cases nicer.

A new test tests for a name setter on every HTML element type. In addition to its overt and upstreamable purpose of checking IDL property reflection semantics, for us this test also hits some Servo assertions that make sure the name is an atom in every case. If the test doesn't crash, even a failed test case still has the attribute as an atom rather than some other type. The failed cases are for elements that we have unimplemented or completely stubbed; I added a few missing name IDL properties to otherwise implemented elements.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #25570 and make progress on #25057

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- [X] There are tests for these changes

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