Sapphire 2.6.002: various user interface improvements

- Echo now has a GAIN control group to adjust the input audio level.
- Chaos modules now have buttons to insert Chaops, Tricorder expanders.
- Tricorder has buttons to insert Tin, Tout expanders.
- Galaxy, Gravy, Elastika now have buttons to configure stereo port behavior.

More details in changelog:

https://github.com/cosinekitty/sapphire/blob/main/CHANGELOG.md

Screen shots and examples:

https://github.com/cosinekitty/sapphire/releases/tag/rc2.6.002.10

plugins/Sapphire

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-Subproject commit ef10da4e2578162b2db2f6534857d6504491daf4
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