refactor outbound sender to allow for multiple modes of dispatch

[piccione99]

also added kinesis and batch packages, but they aren't used yet, please ignore them for reviewing.

OutboundSender contains the common functionality for WebhookOutboundSender and eventually StreamOutboundSender. t

However, OutboundSender has the Update function that takes ancla.Webhook so it doesn't really fit that well with StreamOutboundSender. So, that is a code smell that probably needs to be addressed. That said, we might want to actually update stream senders from Argus so we don't have to reboot caduceus. Initially this will be a predefined set of streams and we need to manually add them to headwaters, so it can't be entirely automated. But would be nice to not have to redeploy caduceus.

[codecov]

Codecov Report

❌ Patch coverage is 64.01180% with 244 lines in your changes missing coverage. Please review.
✅ Project coverage is 55.73%. Comparing base (d496c94) to head (47cbc87).
⚠️ Report is 108 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/kinesis/kinesis.go	41.74%	114 Missing and 6 partials ⚠️
webhook_dispatcher.go	72.62%	40 Missing and 9 partials ⚠️
webhook_outbound_sender.go	72.27%	22 Missing and 6 partials ⚠️
main.go	0.00%	21 Missing ⚠️
stream_dispatcher.go	80.30%	10 Missing and 3 partials ⚠️
internal/stream/sender.go	67.85%	6 Missing and 3 partials ⚠️
stream_outbound_sender.go	89.28%	2 Missing and 1 partial ⚠️
outboundSender.go	90.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #614      +/-   ##
==========================================
+ Coverage   53.89%   55.73%   +1.83%     
==========================================
  Files           9       16       +7     
  Lines        1334     1830     +496     
==========================================
+ Hits          719     1020     +301     
- Misses        574      749     +175     
- Partials       41       61      +20     

Flag	Coverage Δ
unittests	55.73% <64.01%> (+1.83%)	⬆️

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[piccione99]

this is removed

[piccione99]

this will eventually also return StreamOutboundSender