Expose wrapped iterator in SerializationIterator

[yorickvP]

Change Summary

We're currently working around pydantic#8907 by parsing the pointer out of the repr(). To make this workaround slightly better, we'd like to expose the wrapped iterator in SerializationIterator via .iterator.

Related issue number

• Related to: model_dump converts file objects / streams to SerializationIterator pydantic#8907

Checklist

• Unit tests for the changes exist
• Documentation reflects the changes where applicable
• Pydantic tests pass with this pydantic-core (except for expected changes)
• My PR is ready to review, please add a comment including the phrase "please review" to assign reviewers

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.54%. Comparing base (ab503cb) to head (6e3ed61).
Report is 156 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1399      +/-   ##
==========================================
- Coverage   90.21%   89.54%   -0.68%     
==========================================
  Files         106      109       +3     
  Lines       16339    17348    +1009     
  Branches       36       41       +5     
==========================================
+ Hits        14740    15534     +794     
- Misses       1592     1794     +202     
- Partials        7       20      +13     

Files	Coverage Δ
src/serializers/type_serializers/generator.rs	81.39% <ø> (-13.46%)	⬇️

... and 39 files with indirect coverage changes

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 39a6b10...6e3ed61. Read the comment docs.

[yorickvP]

Test failure looks unrelated.

[codspeed-hq]

CodSpeed Performance Report

Merging #1399 will not alter performance

_{Comparing yorickvP:yorickvp/expose-sit-iterator (6e3ed61) with main (39a6b10)}

Summary

✅ 155 untouched benchmarks

[sydney-runkle]

LGTM, let's get a final review by either @davidhewitt or @samuelcolvin.

Thanks for your patience with this review process!