Replace internal OrderedDict usage with dict

[serhii73]

Close #1108

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.10%. Comparing base (373ede9) to head (e1b172a).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1328      +/-   ##
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- Coverage   97.10%   97.10%   -0.01%     
==========================================
  Files         235      235              
  Lines        2904     2899       -5     
==========================================
- Hits         2820     2815       -5     
  Misses         84       84              

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[Copilot]

Pull request overview

This PR aims to modernize the codebase by replacing OrderedDict with plain dict now that supported Python versions preserve insertion order. It touches runtime parsing/loading code, calendar/localization helpers, data-generation scripts, and one ordering-sensitive test, in the context of issue #1108.

Changes:

• Replaces several internal OrderedDict constructions with {}/dict(...) in parser, locale, loader, and date-handling code.
• Updates Jalali calendar metadata and locale-relative translation helpers to use plain dicts.
• Updates CLDR/supplementary data generation scripts and one date parsing test to remove OrderedDict.

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tests/test_date.py	Rewrites an ordering-sensitive test fixture from OrderedDict to dict.
dateparser/utils/__init__.py	Changes combine_dicts() to build a plain dict.
dateparser/parser.py	Replaces directive order containers with plain dicts.
dateparser/languages/locale.py	Replaces relative-translation map construction with a plain dict.
dateparser/languages/loader.py	Replaces locale maps with plain dicts, including get_locale_map().
dateparser/date.py	Changes DateDataParser.previous_locales storage to a plain dict.
dateparser/calendars/jalali_parser.py	Replaces ordered month/weekday maps with dict literals.
dateparser_scripts/write_complete_data.py	Removes OrderedDict from generated-data assembly and file loading.
dateparser_scripts/utils.py	Replaces script-side dict merge/diff helpers with plain dicts.
dateparser_scripts/order_languages.py	Builds the language-locale output map with a plain dict.
dateparser_scripts/get_cldr_data.py	Replaces ordered mappings in CLDR extraction/cleanup with plain dicts.

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[AdrianAtZyte]

The clean, backward-compatible way to approach this is probably to create a special OrderedDict subclass that triggers a warning whenever such methods are used, and after a deprecation period of ~1 year, to start returning a dict instead.

Another approach would be to deprecate the function itself, and implement a new copy of it that uses dict instead of OrderedDict. If this method should not have been a public method in the first place, implementing a _combine_dicts function that uses dict and deprecating the public one is probably the simplest approach.