WIP enh(encryption): Adjust messaging/etc

[joshtrichards]

Fixes #44532
Helps with #43123

Also adds a warning so that people aren't confused when the "Enable server-side encryption" toggle can't be toggled anymore after encryption is enabled.

Fix split out into separate PR while I mess with this other stuff: #44604

• Resolves: #

Summary

TODO

• Add warning that once enabled, encryption cannot be disabled from the web UI (and that's why radio button stays grayed out even once when enabled)
• Add tip/notice about why "Enable server-side encryption" can't be toggled in (because the default encryption module app isn't enabled!)
• Warn if E2E app is active (incompatible with each other currently)

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[joshtrichards]

/compile /

[joshtrichards]

/compile /

[joshtrichards]

/compile /

[github-actions]

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