docs(reasoning): fix broken ExtendedThinkingExample reference by using ReasoningModesExample

[Atharv-navatre]

🐛 Problem

The design document docs/design/phase-4.1-reasoning-modes.md referenced:

org.llm4s.samples.reasoning.ExtendedThinkingExample

However, this class does not exist in the codebase.
Users following the documentation encounter a runtime failure when trying to execute the example.

✅ Changes

• Replaced the missing ExtendedThinkingExample with the existing and runnable:
  ReasoningModesExample
• Kept the Anthropic environment setup unchanged
• Added a note indicating that a dedicated ExtendedThinkingExample is planned for a future update

🎯 Result

• Documentation now reflects the actual implementation
• Example command runs successfully
• Prevents confusion and broken first-time user experience

🧪 Validation

Verified the updated command:

sbt "samples/runMain org.llm4s.samples.reasoning.ReasoningModesExample"

executes correctly.

---

This is a documentation-only change with no impact on runtime behavior.

[github-actions]

🔒 Claude Code Review Status

Thank you for your contribution! This PR is from an external repository, so automated Claude review is disabled for security reasons.

For maintainers: To get Claude review for this PR, comment @claude and I'll trigger a manual review.

PR Summary:

• Files changed: 1
• Additions: +3
• Deletions: -3
• Author: @Atharv-navatre

[Atharv-navatre]

Hi @rorygraves 👋

While following the reasoning modes design doc I noticed that
ExtendedThinkingExample was referenced but not present in the codebase,
which caused the run command to fail for first-time users.

This PR aligns the documentation with the current implementation by
switching to the existing ReasoningModesExample and adding a short
note about the planned dedicated example.

I also verified locally that the updated command runs successfully ✅

Thanks to Piyush Gupta for suggesting this issue — it was a great
doc-alignment task to pick up.

Happy to adjust the wording or split this if a separate
ExtendedThinkingExample is introduced later.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[rorygraves]

Thanks for catching the stale ExtendedThinkingExample reference — the intent here is correct and appreciated.

However, the diff introduces broken markdown formatting that would be worse than the original issue:

1. Stray code fence — Line 117 adds an unmatched ```md that opens a code block but is never closed, causing everything below it to render as a code block instead of normal content.

2. Missing closing fence — The code example that starts around line 123 (````scala) has its closing ``` ` removed or displaced, so the scala code block bleeds into the surrounding text.

To fix:

• Remove the stray ```md on line 117
• Ensure every ``` opener has a matching closer
• Preview the rendered markdown locally before pushing (e.g., with grip or your IDE's markdown preview)

Please also clean up your commit history (amend or squash) before pushing the fix.

[rorygraves]

Re-Review: REQUEST CHANGES

The intent is correct — ExtendedThinkingExample doesn't exist in the codebase; the correct class is ReasoningModesExample. However, the previous review feedback has not been addressed. The same markdown formatting regressions remain:

Issues

1. Hunk 1 removes the closing ``` fence (line 71) for the Scala code block that opens at line 44. This causes the entire "Provider Mapping" table and subsequent content to render inside a code block — a significant rendering regression.

2. Hunk 3 inserts a stray ```md fence before the list item, opening a code block that is never closed. Everything from that point forward (Success Criteria, Future Enhancements) renders as raw unformatted code.

3. Hunk 3 removes the closing ``` fence for the bash code block without replacing it, leaving the bash block unclosed.

What needs to happen

The fix should only change the ExtendedThinkingExample references to ReasoningModesExample — no other lines should be modified. The code fence structure must remain intact. Please:

1. Start fresh from main
2. Only modify the lines containing ExtendedThinkingExample
3. Verify the markdown renders correctly before pushing

[Atharv-navatre]

Thanks for the detailed review, @rorygraves!

I’ve removed the stray code fence and restored proper code block boundaries so that every opening fence now has a matching closing fence.

I also previewed the rendered markdown locally to verify the formatting and ensure that only the intended sections render as code blocks.

Additionally, I amended the commit to keep the history clean as requested.

Please take another look — this should now be good to go. Thanks again for the guidance!

[vim89]

@claude

[Atharv-navatre]

Thanks @vim89 @rorygraves for the detailed review!

Restored the missing closing code fence so all code blocks now render correctly and verified the markdown preview locally.

The diff is now limited to the intended change and the fence fix only.

Please take another look 🙏