refactor: Split message send/edit types/documentation

[Jiralite]

Please describe the changes this PR makes and why it should be merged:
Some general refactoring around sending and editing messages. For example, attachments showed up when sending a message when it should not - it should appear when editing. This also resolves #8587.

• Code changes have been tested against the Discord API, or there are no code changes
• I know how to update typings and have done so, or typings don't need updating

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1 Ignored Deployment

Name	Status	Preview	Updated
discord-js	⬜️ Ignored (Inspect)		Sep 11, 2022 at 6:16PM (UTC)

[codecov]

Codecov Report

Merging #8590 (15c4b12) into main (4ffdada) will decrease coverage by 0.00%.
The diff coverage is n/a.

❗ Current head 15c4b12 differs from pull request most recent head 4b19cce. Consider uploading reports for the commit 4b19cce to get more accurate results

@@            Coverage Diff             @@
##             main    #8590      +/-   ##
==========================================
- Coverage   86.47%   86.47%   -0.01%     
==========================================
  Files          87       87              
  Lines        8675     8679       +4     
  Branches     1110     1110              
==========================================
+ Hits         7502     7505       +3     
- Misses       1131     1132       +1     
  Partials       42       42              

Flag	Coverage Δ
builders	100.00% <ø> (ø)
collection	100.00% <ø> (ø)
proxy	74.10% <ø> (ø)
rest	92.00% <ø> (+<0.01%)	⬆️
utilities	100.00% <ø> (ø)
voice	63.86% <ø> (ø)
ws	60.42% <ø> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
packages/voice/src/VoiceConnection.ts	81.76% <0.00%> (ø)
packages/voice/src/networking/Networking.ts	3.18% <0.00%> (ø)
packages/voice/src/receive/VoiceReceiver.ts	90.56% <0.00%> (ø)
packages/rest/src/lib/errors/DiscordAPIError.ts	96.46% <0.00%> (+0.03%)	⬆️
packages/ws/src/ws/WebSocketShard.ts	23.32% <0.00%> (+0.22%)	⬆️

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