[RishavTiwari25]

Summary

Two related bugs in TranscriptionConfig / Transcript.config.

1. TranscriptionConfig(raw_transcription_config=raw) erased almost all of raw's values.
The constructor stored raw and then ran every setter (self.language_code = language_code, self.punctuate = punctuate, ...) with the arguments' None defaults, writing straight onto raw. So

raw = aai.RawTranscriptionConfig(language_code="de", punctuate=False)
aai.TranscriptionConfig(raw_transcription_config=raw).language_code  # None

and raw itself was mutated to language_code=None, punctuate=None. The docstring says explicit arguments should take priority over the raw config, not wipe it.

2. transcript.config raised for some completed transcripts.
config_from_response passed the response's fields as TranscriptionConfig(**fields). That breaks when a field's API shape differs from the constructor argument, or the field is not an argument at all:

• custom_spelling: the API echoes [{"from": [...], "to": "..."}], but set_custom_spelling expects a {to: from} dict -> AttributeError: 'list' object has no attribute 'items'.
• language_detection_results: a RawTranscriptionConfig field but not a constructor argument -> TypeError: unexpected keyword argument.

Changes

• assemblyai/types.py: the constructor applies the explicit arguments to a fresh RawTranscriptionConfig, then copies only the non-None ones onto the passed raw_transcription_config (explicit arguments still win) and keeps that object.
• assemblyai/prerecorded/v2/_base.py: config_from_response builds a RawTranscriptionConfig from the response fields and passes it as raw_transcription_config (this relies on fix 1).
• assemblyai/__version__.py: 1.8.2 -> 1.8.3 for the version bump check.

Tests

• tests/unit/test_config.py: raw values are kept (incl. punctuate=False and custom_spelling); explicit arguments override raw values while the rest are kept.
• tests/unit/test_transcript.py: transcript.config for a response with custom_spelling and one with language_detection_results.

All four fail on master and pass with the fix. pytest tests/unit: 923 passed, 1 failure that also fails on master on Windows (test_upload_request_omits_content_length_for_an_unsized_stream, unrelated). ruff check / ruff format --check clean on the changed files; mypy reports no new errors.