Add speech rules for black circled Latin letters (U+1F150–1F169)

[brichwin]

Faculty use circled capital letters (U+24B6–U+24CF) to create bubble-sheet like multiple-choice layouts for Gradescope-graded exams in LaTeX. The filled/black circled variants (U+1F150–1F169) are used in solution files to indicate the correct answer.

MathCAT already handled the open circled letters but was missing the black circled versions, leaving the correct-answer indicators unspoken.

This PR adds entries for U+1F150–1F169 to the following locale rule files, following the existing patterns in each:
de, en, es, fi, fr, nb, sv, vi, zh-tw

Translations were made by examining the other black circled character translations and then verifying with translate.google.com by testing speech text from:

<math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
  <mtext>Ⓐ</mtext>
  <mtext>🅐</mtext>
</math>