feat: support proxy with grpc-only mode

[mmsqe]

Description

depends on cosmos/cosmos-sdk#25565, for test info

---

Author Checklist

All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.

I have...

• tackled an existing issue or discussed with a team member
• left instructions on how to review the changes
• targeted the main branch

[codecov]

Codecov Report

❌ Patch coverage is 45.45455% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 65.30%. Comparing base (d97c9e5) to head (78941cf).

Files with missing lines	Patch %	Lines
server/start.go	0.00%	3 Missing ⚠️
server/config/config.go	50.00%	1 Missing and 1 partial ⚠️
ante/cosmos/eip712.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #815      +/-   ##
==========================================
+ Coverage   65.20%   65.30%   +0.09%     
==========================================
  Files         317      317              
  Lines       21614    21586      -28     
==========================================
+ Hits        14094    14096       +2     
+ Misses       6360     6329      -31     
- Partials     1160     1161       +1     

Files with missing lines	Coverage Δ
ante/evm/fee_checker.go	71.83% <100.00%> (ø)
ethereum/eip712/encoding.go	78.18% <100.00%> (ø)
ethereum/eip712/encoding_legacy.go	75.18% <100.00%> (ø)
rpc/backend/account_info.go	85.71% <ø> (ø)
ante/cosmos/eip712.go	3.10% <0.00%> (ø)
server/config/config.go	46.80% <50.00%> (+0.09%)	⬆️
server/start.go	0.00% <0.00%> (ø)

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[aljo242]

why is it ok to remove all of this?

[mmsqe]

since we can replace with sdk StartGrpcServer?