Add OpenCode client support

[prestist]

So I was using opencode, and wanted to have integration for MCP servers. I think this is all that is needed.

I tested this locally

./thv client status
./thv client register opencode

Then ran a mcp server

./thv run context7

opencode
verified mcp server present. 

Not sure if there are other steps for integration of opencode.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 55.34%. Comparing base (d7decc7) to head (8794eb4).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2489   +/-   ##
=======================================
  Coverage   55.34%   55.34%           
=======================================
  Files         306      306           
  Lines       29321    29321           
=======================================
  Hits        16227    16227           
- Misses      11657    11658    +1     
+ Partials     1437     1436    -1     

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[eleftherias]

Thanks @prestist! This looks good.
I see there are some small linting issues, could you just run task lint to see the lint errors and task docs to update the CLI docs?

[prestist]

Thank you, absolutely will do! @eleftherias

[prestist]

@eleftherias I looked at the taskfile and ran linting / created the docs I think; lmk if there is anything else! Thank you.

Oof, ok I see I missed a few; I cannot run golang-lint ci locally due to some config weird, Let me make the changes listed in the CI real quick.

The doc's bit supersized me though; looking again

[prestist]

Hmm, im still struggling with running linting locally tried my hand with AI here to see if it can figure out my environment. 🤞

[eleftherias]

No worries @prestist, I can generate the docs. No point in you spending time with minor linting issues.

[eleftherias]

Thanks for the PR @prestist!