Corrections and additions for Punjabi Shahmukhi (Arabic script)

[bgo-eiu]

These updates are concerned with correcting the set of characters used for the language. When I have time in the future, I will add sample text as well that mirrors that of the Punjabi Gurmukhi file. Thank you

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[moyogo]

@bgo-eiu The data originally comes from the CLDR https://github.com/unicode-org/cldr/blob/aa0dd5acb1e68876c730e90ef6cb43cfc4d7006f/common/main/pa_Arab.xml#L32-L36.

These changes look likes they are replacing ڻ used in Panjabi [pa] by ‎ݨ which is used in Saraiki [skr] or Western Panjabi [pnb], and adding ࣇ which is used in Western Panjabi [pnb].
Note that Panjabi [pa] in ISO 639-1 is called "Eastern Panjabi" in Ethnologue and Panjabi [pan] in ISO 639-3).

Should these changes be a separate language data file for Western Panjabi pnb_Arab.textproto?

If this is indeed for Eastern Panjabi [pan], do you have a reference.
Elena Bashir and Thomas J. Conners, with Brook Hefright, A Descriptive Grammar of Hindko, Panjabi, and Saraiki, 2019, p. 65 indicates ݨ is used in Saraiki and ن is used in Panjabi.

Lorna Priest Evans and M. G. Abbas Malik, Proposal to encode ARABIC LETTER LAM WITH SMALL ARABIC LETTER TAH ABOVE in the UCS, 2019 shows ݨ being used in Punjabi but it does indicate Western Punjabi uses the Arabic script (Shahmukhi) and hasn’t been standardized.

I’m leaning towards creating a separate file for Western Panjabi [pnb].