Streamline built-in speech dictionary rules

source/builtin.dic

@@ -1,6 +1,6 @@
-#break up words that use a capital letter to denote another word
-([a-z])([A-Z])	\1 \2	1	1
-#Break away a word starting with a capital from a fully uppercase word
-([A-Z])([A-Z][a-z])	\1 \2	1	1
-#Break words that have numbers at the end
-((?:(?=\D)\w)+)(\d+)	\1 \2	1	1
+#Break up words that use a capital letter to denote another word
+(?=[A-Z])(?<=[a-z])	 	1	1
+#Break away a word starting with a capital from a fully uppercase word
+(?=[A-Z][a-z])(?<=[A-Z])	 	1	1
+#Break on word-to-digit boundaries
+(?=\d)(?<=[^\W\d])	 	1	1

user_docs/en/changes.md

@@ -30,6 +30,7 @@
 * In PowerPoint and other Office applications, NVDA will now correctly read and navigate the edit fields in the insert hyperlink dialog. (#17390, @aryanchoudharypro)
 * The actions button can now be used when selecting multiple add-ons in the Add-on Store to perform batch actions, instead of just via the context menu in the add-ons list. (#19971, @amirmahdifard)
 * When moving to an ARIA grid cell in focus mode in web browsers, NVDA no longer reports both the row and column headers even if only the row or only the column changed. (#17750, @jcsteh)
+* Improved speech responsiveness when processing long text with mixed capitalization or many digits. (#20433, @codeofdusk)
 * In live text regions, such as terminals, NVDA no longer freezes when substantial amounts of text are dumped to the screen. (#20177, #20216, @ethindp, @codeofdusk)
 * When an application stops responding, NVDA no longer freezes or floods its log with errors; it stays responsive and drops UIA and MSAA events from the unresponsive application until it recovers. (#16749, @heath-toby)
 * Reduced lag on UI Automation text change events, improving the responsiveness of controls such as combo boxes and of File Explorer, by using the cached element class name instead of a live cross-process fetch. (#16749, @heath-toby)