This change is reduce Ruby C API dependency for Universal Parser.
Reuse dedent_string functions in rb_ruby_ripper_dedent_string functions and remove dependencies on rb_str_modify and rb_str_set_len from the parser.
Recently, `TestRubyLiteral#test_float` fails randomly.
```
1) Error:
TestRubyLiteral#test_float:
ArgumentError: SyntaxError#path changed: "(eval at /home/chkbuild/chkbuild/tmp/build/20240527T050036Z/ruby/test/ruby/test_literal.rb:642)"->"(eval at /home/chkbuild/chkbuild/tmp/build/20240527T050036Z/ruby/test/ruby/test_literal.rb:642)"
```
https://rubyci.s3.amazonaws.com/s390x/ruby-master/log/20240527T050036Z.fail.html.gz
According to Launchable, the first failure was on Apr 30.
This is just when 528c4501f46fbe1e06028d673a777ef124d29829 was
committed. I don't know if the change is really the cause, but I want to
revert it once to see if the random failure disappears.
This commit simplifies warnings for hash keys duplication and when clause duplication,
based on the discussion of https://bugs.ruby-lang.org/issues/20331.
Warnings are reported only when strings are same to ohters.
- Introduce `rb_parser_ary_t` structure to partly eliminate RArray from parse.y
- In this patch, `parser_params->tokens` and `parser_params->ast->node_buffer->tokens` are now `rb_parser_ary_t *`
- Instead, `ast_node_all_tokens()` internally creates a Ruby Array object from the `rb_parser_ary_t`
- Also, delete `rb_ast_tokens()` and `rb_ast_set_tokens()` in node.c
- Implement `rb_parser_str_escape()`
- This is a port of the `rb_str_escape()` function in string.c
- `rb_parser_str_escape()` does not depend on `VALUE` (RString)
- Instead, it uses `rb_parser_stirng_t *`
- This function works when --dump=y option passed
- Because WIP of the universal parser, similar functions like `rb_parser_tokens_free()` exist in both node.c and parse.y. Refactoring them may be needed in some way in the future
- Although we considered redesigning the structure: `ast->node_buffer->tokens` into `ast->tokens`, we leave it as it is because `rb_ast_t` is an imemo. (We will address it in the future)
String nodes holds ruby string object on `VALUE nd_lit`.
This commit changes it to `struct rb_parser_string *string`
to reduce dependency on ruby object.
Sometimes these strings are concatenated with other string
therefore string concatenate functions are needed.
NODE_ARGS, NODE_ARYPTN, NODE_FNDPTN manage memory of their
structure by imemo tmpbuf Object.
However rb_ast_struct has reference to NODE. Then these
memory can be freed directly when rb_ast_struct is freed.
This commit reduces parser's dependency on CRuby functions.
