Make more types jl_static_show unambiguously (#58512)
Makes more types survive `jl_static_show` unambiguously:
- Symbols
- Symbols printed in the `:var"foo"` form use raw string escaping,
fixing `:var"a\b"`, `:var"a\\"`, `:var"$a"`, etc.
- Symbols that require parens use parens (`:(=)`, ...)
- Signed integers: Except for `Int`, signed integers print like
`Int8(1)`.
- Floats: floats are printed in a naive but reversible (TODO: double
check) way. `Inf(16|32|)` and `NaN(16|32|)` are printed, and
`Float16`/`Float32` print the type (`Float32(1.5)`). `Float64`s are
printed with a trailing `.0` if it is necessary to disambiguate from
`Int`.
Fixes #52677,
https://github.com/JuliaLang/julia/issues/58484#issuecomment-2902468354,
https://github.com/JuliaLang/julia/issues/58484#issuecomment-2898733637,
and the specific case mentioned in #58484. Improves the situation for
#38902 but does not close it, because a few cases still do not
round-trip (inexhaustive list):
- Non-canonical NaNs
- BFloat16
- User-defined primitive types. This one is tricky, because they can
have a size different from any type we have literals for.
