feat: support gRPC with connect-rpc

[laststylebender14]

Summary:
Briefly describe the changes made in this PR.

Issue Reference(s):
Fixes #... (Replace "..." with the issue number)

Build & Testing:

• I ran cargo test successfully.
• I have run ./lint.sh --mode=fix to fix all linting issues raised by ./lint.sh --mode=check.

Checklist:

• I have added relevant unit & integration tests.
• I have updated the documentation accordingly.
• I have performed a self-review of my code.
• PR follows the naming convention of <type>(<optional scope>): <title>

[codecov]

Codecov Report

Attention: Patch coverage is 99.35484% with 1 line in your changes missing coverage. Please review.

Project coverage is 86.73%. Comparing base (607d52f) to head (89f9d6c).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/core/generator/proto/connect_rpc.rs	99.29%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3197      +/-   ##
==========================================
+ Coverage   86.66%   86.73%   +0.06%     
==========================================
  Files         277      278       +1     
  Lines       27761    27909     +148     
==========================================
+ Hits        24059    24206     +147     
- Misses       3702     3703       +1     

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