feat: Update README with highlights and getting started guide

[kylecarbs]

No description provided.

[codecov]

Codecov Report

Merging #627 (aadf806) into main (13cef7d) will decrease coverage by 0.07%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #627      +/-   ##
==========================================
- Coverage   63.65%   63.57%   -0.08%     
==========================================
  Files         197      197              
  Lines       11537    11537              
  Branches       85       85              
==========================================
- Hits         7344     7335       -9     
- Misses       3416     3423       +7     
- Partials      777      779       +2     

Flag	Coverage Δ
unittest-go-	62.56% <ø> (-0.13%)	⬇️
unittest-go-macos-latest	58.47% <ø> (ø)
unittest-go-ubuntu-latest	61.60% <ø> (+0.09%)	⬆️
unittest-go-windows-2022	57.65% <ø> (+0.04%)	⬆️
unittest-js	63.32% <ø> (ø)

Impacted Files	Coverage Δ
peerbroker/dial.go	75.43% <0.00%> (-7.02%)	⬇️
coderd/workspaceresources.go	59.72% <0.00%> (-1.81%)	⬇️
provisionerd/provisionerd.go	80.02% <0.00%> (-0.59%)	⬇️
coderd/provisionerdaemons.go	59.73% <0.00%> (-0.51%)	⬇️
peer/conn.go	78.93% <0.00%> (+0.76%)	⬆️
provisionersdk/serve.go	43.24% <0.00%> (+8.10%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 13cef7d...aadf806. Read the comment docs.

[bpmct]

I was gonna nit on the messaging a bit, but decided it'd be more productive once we create a messaging doc. I like the placement of these here 👍🏼

[kylecarbs]

Yeah, we can totally change these whenever. Feel free to nit on em' now if you'd like. I'm all ears!

[ammario]

I think we can make these a lot more compelling but I'll wait to invest until Ben takes a pass.

[ammario]

This is a good first iteration