Stop sending reply and edit fallbacks (MSC2781)

[aaronraimist]

Fixes https://github.com/vector-im/element-web/issues/20334 Fixes https://github.com/vector-im/element-web/issues/7874 Fixes https://github.com/vector-im/element-web/issues/7014

Implementation of MSC2781 https://github.com/matrix-org/matrix-doc/pull/2781

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This change is marked as an internal change (Task), so will not be included in the changelog.

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[HarHarLinks]

while I agree the ecosystem needs to adapt, I think it's much easier to support events without than with fallbacks also for bots just as it is for client( sdk)s. What's the plan to push towards it? Labs flag for this and test around how it goes? Announce to everyone to implement this MSC before it gets merged while retaining compatibility with fallbacks with a deadline?

[turt2live]

See also: MSC2781

[weeman1337]

Conversion to a draft, as we are still waiting for mobile. We should reopen it if there is a chance to move it forward.

(see Oldest non-draft PR from last Web Weekly)