1.8.9.1 change mode within story

[JackMostow]

This issue succeeds READ add PARROT, HIDE, REVEAL #262.

Allow story mode to change sentence by sentence, so that we can, e.g., insert spoken prompts.

Which is easier to implement and use?

a. Treat story mode as a variable that storydata.json can assign a new value.
+: simple
+: concise
-: context-dependent because its scope lasts until the next assignment

b. Treat story mode as a nestable modifier to wrap around one or more pages or sentences.
+: context-independent insofar as it's not affected by changing the mode of the preceding text
-: verbose
-: modifier could nest around multiple pages, which might be awkward

[JackMostow]

This is an architectural change, so it involves Kevin, but may be appropriate for Octav to implement.

[JackMostow]

If animator graph for story does a case split on mode, or mode is a feature, storydata.json can signal which words to narrate from which package, e.g. generic prompts vs. story text.

[JackMostow]

Octav - Please implement per-sentence modes.
Ulani - As consumer for this feature, please let Octav know which syntax will make your task easier.