Work around JRuby absolute_path bug on load with bare relative path.

JRuby's `Thread::Backtrace::Location#absolute_path` returns a relative
path (same as `#path`) when the file was loaded via `load "file.rb"`
(bare relative, no `./` prefix). MRI correctly resolves to full absolute
path. This broke `Pathname#relative_path_from` in schema_artifact_manager.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: myronmarston

elasticgraph-schema_definition/lib/elastic_graph/schema_definition/jruby_patches.rb

@@ -16,6 +16,22 @@
 # Reported upstream: https://github.com/jruby/jruby/issues/9242
 # TODO: remove once JRuby fixes this upstream.
 
+# Bug: `Thread::Backtrace::Location#absolute_path` returns a relative path (same as `#path`)
+# when the source file was loaded via `load` with a bare relative path (e.g. `load "schema.rb"`).
+# On MRI, `absolute_path` correctly resolves to the full absolute path in this case.
+# Workaround: override `absolute_path` to expand relative paths.
+# Reported upstream: https://github.com/jruby/jruby/issues/XXXX
+# TODO: remove once JRuby fixes this upstream.
+class ::Thread::Backtrace::Location
+  alias_method :__original_absolute_path__, :absolute_path
+
+  def absolute_path
+    result = __original_absolute_path__
+    return result if result.nil? || result.start_with?("/")
+    ::File.expand_path(result)
+  end
+end
+
 require "elastic_graph/schema_definition/mixins/has_indices"
 
 module ElasticGraph

elasticgraph-schema_definition/lib/elastic_graph/schema_definition/schema_artifact_manager.rb

@@ -15,6 +15,10 @@
 require "tempfile"
 require "yaml"
 
+# :nocov: -- only loaded on JRuby
+require "elastic_graph/schema_definition/jruby_patches" if RUBY_ENGINE == "jruby"
+# :nocov:
+
 ElasticGraph::Support::GraphQLGemLoader.load
 
 module ElasticGraph