Fix duplicate comment output when method chain has block

[fs0414]

📋 Summary

Fixes a bug where inline comments were duplicated in the output when formatting code with chained method calls that include blocks.

Before (bug):

# Input
some_method # comment
  .method_with_block { do_something }

# Output (incorrect - comment duplicated)
some_method # comment
  .method_with_block { do_something }
# comment  ← duplicated

After (fixed):

# Input = Output (no change, already formatted)
some_method # comment
  .method_with_block { do_something }

🔧 Changes

Core Fix

• emit_call_without_block(): Added logic to mark comments within the extracted source range as emitted, preventing duplicate output in subsequent processing

Root Cause

When emit_call_without_block() extracts source text from call_node.start_offset to block_node.start_offset, inline comments are included in the extracted text. However, these comments were not being marked in emitted_comment_indices, causing them to be output again by later comment-handling routines.

Test Coverage

• Added 2 test cases covering:
  • Method chain with brace block ({ })
  • Method chain with do-end block

🗂️ Changed Files

• Rust emitter: ext/rfmt/src/emitter/mod.rs
• Tests: spec/rfmt_spec.rb

🧪 Testing

Test Execution

bundle exec rspec

Results

• 89 examples, 0 failures
• No regressions

Verification

• Bug reproduction confirmed before fix
• New tests pass after fix
• All existing tests pass (regression check)
• Manual verification with rfmt --diff

📦 Breaking Changes

None

Related Issue

Closes #85