rcv: Improve CSV parsing preprocessing and logging

[svillegas-cdd]

• Implement preprocessing for required fields in CSV parsing
• Improve error handling for CSV row data conversion

Ref: https://app.shortcut.com/cordada/story/15534/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.82%. Comparing base (d627525) to head (4d74644).
Report is 2 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #838      +/-   ##
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+ Coverage    87.43%   87.82%   +0.38%     
===========================================
  Files           38       38              
  Lines         3176     3187      +11     
  Branches       321      323       +2     
===========================================
+ Hits          2777     2799      +22     
+ Misses         257      249       -8     
+ Partials       142      139       -3     

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[sonarqubecloud]

Quality Gate passed

Issues
4 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
2.5% Duplication on New Code

See analysis details on SonarQube Cloud

[Copilot]

Pull Request Overview

This PR enhances CSV parsing by stripping out empty required fields before schema validation and improving error handling/logging for row conversion failures.

• Introduces a preprocess hook to remove empty or null required fields prior to validation.
• Refactors conversion exception logging to include row index and renames the error key to conversion_errors.
• Adds unit tests and a CSV fixture to verify missing required fields and conversion errors in the “venta” parser.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/tests/test_rcv_parse_csv.py	Added tests for missing required fields and conversion error scenarios in parse_rcv_venta_csv_file.
src/tests/test_data/sii-rcv/RCV-venta-missing-required-fields.csv	New CSV fixture with intentionally empty required fields for testing preprocessing logic.
src/cl_sii/rcv/parse_csv.py	Implemented preprocess to strip empty required fields and improved conversion error logging and error-key naming.

Comments suppressed due to low confidence (2)

src/cl_sii/rcv/parse_csv.py:1201

• [nitpick] The key 'conversion_errors' is plural but holds a single error string; consider renaming it to 'conversion_error' or storing a list of errors to match the plural form.

                row_errors['conversion_errors'] = conversion_error

src/tests/test_rcv_parse_csv.py:157

• This test is currently a stub and does not validate any behavior; consider implementing tests for missing required fields and conversion errors in the 'compra' CSV parsing to match the coverage added for 'venta'.

    def test_parse_rcv_compra_registro_csv_file(self) -> None: