feat!(timeline): allow sending media as (thread) replies

[Johennes]

This implements step 3 of #4835.

• Public API changes documented in changelogs (optional)

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 2 lines in your changes missing coverage. Please review.

Project coverage is 86.56%. Comparing base (d30dc71) to head (45bdaa1).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/matrix-sdk/src/send_queue/upload.rs	84.61%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4852   +/-   ##
=======================================
  Coverage   86.55%   86.56%           
=======================================
  Files         300      300           
  Lines       34966    34980   +14     
=======================================
+ Hits        30266    30281   +15     
+ Misses       4700     4699    -1     

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[Johennes]

I've added this here to not have to duplicate the send_* methods for the various media types. Maybe we could also use this to merge send_reply and send_thread_reply?

[bnjbvr]

Yep, that would make sense (maybe as a followup PR, to not have this one drag for too long?)

[Johennes]

Separate PR makes sense. 👍

[bnjbvr]

Thanks! A first round of review comments here, but it looks like this is on the right track!

[bnjbvr]

Nice, we're getting close to landing this! LGTM on principle that we can address the last comments without large changes.

[bnjbvr]

Yep, that would make sense (maybe as a followup PR, to not have this one drag for too long?)

[Johennes]

Thanks a lot for your patience with me figuring things out through multiple rounds of review here. 🙏

[bnjbvr]

No worries, thanks a lot for this contribution!