Split out experimental analysis

[ekpyron]

Split out a first batch of technical infrastructure of #14510 into a PR targetting develop.

Parts that should go into the new PR:

• The new scanner kind ScannerKind::ExperimentalSolidity and the surrounding scanner changes (including the small change to libyul/AsmParser). Only the tokens NonExperimentalEnd and ExperimentalEnd need to be extracted.
• A stub version of experimental/analysis/Analysis without any annotation logic and with only a check function that always reports an error "experimental analysis not yet implemented" and returns false.
• The changes to CompilerStack, i.e. a special path for experimental solidity, invoking `experimental/analysis/Analysis``
  • Including the assertion in CompilerStack::compile and a similar assertion in CompilerStack::generateIR (instead of invoking experimental::IRGenerator just put in a failing assertion as well)

What does not have to be moved right away:

• Additional tokens
• Changes to the parser
• Changes to the NameAndTypeResolver and ReferenceResolver
• Generally, none of the changes to the currnet analysis steps (like in SyntaxChecker)
• The additional AST nodes and their annotations and visitor logic
• The actual logic of experimental/analysis/Analysis.* - we can start from a stub that just always fails, see above
• The actual analysis steps in experimental/analysis/*
• Code generation or AST experimental/ast, experimental/codegen

This will cause the existing experimental solidity import tests to fail, but that's fine to accept on develop for now.