Add error position and json_path to the JRuby extension

[ojuschugh1]

Follow-up to #1062, as suggested there: this brings ParserError#line, #column and #json_path to the JRuby extension.

The Java parser already shares the C parser's architecture (frame stack + value stack), so the implementation mirrors it closely: positions are computed by scanning backwards from the error offset like cursor_position does in C, and @json_path is collected as raw segments from the frame stack, then formatted by the shared Ruby code from #1062. Everything happens at raise time, so nothing is added to the happy path. NestingError stays bare, matching the C extension.

Positions and paths come out identical to the C parser:

**jruby 10.0.2.0**
unexpected token at 'xyz}]}}' at line 1 column 34
line=1 column=34 json_path=$.user.roles[1].admin
duplicate key "c" at line 1 column 17
line=1 column=17 json_path=$.a.b[1].c

​
The duplicate key case reuses the existing cursor rewind to the object's opening brace, so line/column match C exactly there too. Error message wording still differs between the two extensions ("unexpected token at" vs "unexpected character:"); I left that alone to keep the diff focused.

The four json_path test methods now run on JRuby (omit guards removed), plus a new test_parse_error_position asserting line/column values on both extensions. JRuby suite goes from 53 omissions to 49 with 0 failures; CRuby stays at 0 failures, 0 omissions.

[ojuschugh1]

Hey @byroot could you kindly review this.

[byroot]

Uh, no idea what I haven't seen this until now.

[headius]

Why did coverage need to be disabled?

[byroot]

Why did coverage need to be disabled?

You can see the failing builds on the first commit.

LoadError: cannot load such file -- prism
           require at org/jruby/RubyKernel.java:1384
   replace_require at /home/runner/.rubies/jruby-10.1.1.0/lib/ruby/stdlib/bundled_gems.rb:81
            <main> at /home/runner/work/json/json/vendor/bundle/jruby/4.0.0/gems/simplecov-1.3.0/lib/simplecov/static_coverage_extractor.rb:3
           require at org/jruby/RubyKernel.java:1384
  require_relative at org/jruby/RubyKernel.java:1408
            <main> at /home/runner/work/json/json/vendor/bundle/jruby/4.0.0/gems/simplecov-1.3.0/lib/simplecov/source_file.rb:4
           require at org/jruby/RubyKernel.java:1384
  require_relative at org/jruby/RubyKernel.java:1408
            <main> at /home/runner/work/json/json/vendor/bundle/jruby/4.0.0/gems/simplecov-1.3.0/lib/simplecov.rb:175
           require at org/jruby/RubyKernel.java:1384
   replace_require at /home/runner/.rubies/jruby-10.1.1.0/lib/ruby/stdlib/bundled_gems.rb:81
            <main> at /home/runner/work/json/json/test/json/test_helper.rb:14
           require at org/jruby/RubyKernel.java:1384
  require_relative at org/jruby/RubyKernel.java:1408
            <main> at /home/runner/work/json/json/test/json/json_coder_test.rb:3
           require at org/jruby/RubyKernel.java:1384
   replace_require at /home/runner/.rubies/jruby-10.1.1.0/lib/ruby/stdlib/bundled_gems.rb:81
            <main> at /home/runner/work/json/json/vendor/bundle/jruby/4.0.0/gems/rake-13.4.2/lib/rake/rake_test_loader.rb:21
            select at org/jruby/RubyArrayNative.java:2488
            <main> at /home/runner/work/json/json/vendor/bundle/jruby/4.0.0/gems/rake-13.4.2/lib/rake/rake_test_loader.rb:6
rake aborted!

[ojuschugh1]

Hey @byroot thanks for the quick review and approval.

No it is not your fault, the thing the github automated algo falsely flagged my github account , so my github account, repo etc were not visible to other, even though i raised my PR for this follow fix, but still is was not showing to others and as I am not a prod users , so it took more than 2 weeks to get their human support for get my account back :(

[headius]

You can see the failing builds on the first commit.

Ah, so it is not including prism as a gem dependency and expecting it to just be available. We don't include prism in the box yet because JRuby is cross-platform and prism requires a native library. If it were in a Gemfile, it would install and work just fine.

I'm working on shipping a cross-platform version using wasm but it's not ready yet.

It would probably be healthy to include it as an explicit dependency.