Add IPA localization forms for Greek Lower Beta/Chi. (#2175)

* Add IPA localization forms for `grek/{beta|chi}`.

* simplify

* doc

* temp fix

* doc

changes/28.0.7.md

@@ -1 +1,2 @@
 * Make superscript/subscript/overscript Cyrillic characters obey localization forms of base letters (#2177).
+* Add IPA localization forms for Greek Lower Beta (`β`) and Chi (`χ`).

packages/font-otl/src/gsub-locl.ptl

@@ -14,6 +14,8 @@ export : define [buildLOCL gsub para glyphStore] : begin
 	define cyrlMKD  : gsub.copyLanguage 'cyrl_MKD ' 'cyrl_DFLT'
 	define cyrlBGR  : gsub.copyLanguage 'cyrl_BGR ' 'cyrl_DFLT'
 	define latnVIT  : gsub.copyLanguage 'latn_VIT ' 'latn_DFLT'
+	define grekIPPH : gsub.copyLanguage 'grek_IPPH ' 'grek_DFLT'
+	define grekAPPH : gsub.copyLanguage 'grek_APPH ' 'grek_DFLT'
 
 	# SRB
 	define loclSRB : gsub.createFeature 'locl'
@@ -61,4 +63,14 @@ export : define [buildLOCL gsub para glyphStore] : begin
 					{'breveAbove'}            ~> nothing
 					viShiftableMarks          ~> [sx 'viCenter']
 
+	# IPPH
+	define loclIPPH : gsub.createFeature 'locl'
+	grekIPPH.addFeature loclIPPH
+	grekAPPH.addFeature loclIPPH
+	loclIPPH.addLookup : gsub.createLookup
+		.type 'gsub_single'
+		.substitutions : object
+			'grek/beta' : glyphStore.ensureExists 'latn/beta'
+			'grek/chi'  : glyphStore.ensureExists 'latn/chi'
+
 	gsub.endBlockAtFront rec

tools/generate-samples/src/templates/languages.mjs

@@ -3,7 +3,7 @@ import * as themes from "../themes/index.mjs";
 // prettier-ignore
 const languages = [
     { lang: 'English', sample: 'Shaw, those twelve beige hooks are joined if I patch a young, gooey mouth.' },
-    { lang: 'IPA', sample: '[ɢʷɯʔ.nas.doːŋ.kʰlja] [ŋan.ȵʑi̯wo.ɕi̯uĕn.ɣwa]' },
+    { lang: 'IPA', sample: '[ɢʷɯʔ.nas.doːŋ.kʰlja] [ŋan.ȵʑi̯wo.ɕi̯uĕn.ɣwa]', localeId :'en-fonipa' },
     { lang: 'Azerbaijani', sample: 'Zəfər, jaketini də papağını da götür, bu axşam hava çox soyuq olacaq.' },
     { lang: 'Belarusian', sample: 'У Іўі худы жвавы чорт у зялёнай камізэльцы пабег пад’есці фаршу з юшкай.' },
     { lang: 'Bulgarian', sample: 'Я, пазачът Вальо уж бди, а скришом хапва кюфтенца зад щайгите.', localeId :'bg' },