Fix translation loss during catalog updates

[BenYang12]

Changes proposed in this pull request:

• Restore extraction of apnumber() words and contextual ordinal() suffixes lost after
  Performance improvements: 1.07x - 8.4x #315, preserving existing translation keys and runtime locale switching.
• Update the translation script and README to recognize the new contextual no-op marker.
• Add German and French regression tests covering catalog updates. Both fail on original
  code; the fixed suite passes all 800 tests. Lint, mypy, docs build, and whitespace checks
  pass.

Related: #83 addressed a separate translation-extraction problem.

Additional source doctests expose one unrelated naturaldelta() example failure,
identical before and after this change.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.69%. Comparing base (e46732e) to head (fd6236b).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #391      +/-   ##
==========================================
+ Coverage   99.57%   99.69%   +0.11%     
==========================================
  Files          12       12              
  Lines         944      980      +36     
==========================================
+ Hits          940      977      +37     
+ Misses          4        3       -1     

Flag	Coverage Δ
macos-latest	97.55% <97.50%> (+0.09%)	⬆️
ubuntu-latest	97.55% <97.50%> (+0.09%)	⬆️
windows-latest	93.16% <40.00%> (-2.18%)	⬇️

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