Git Source Handler for MCPRegistry

[dmartinol]

Fixes: #1924

[coveralls]

Changes unknown
when pulling fb6083e on dmartinol:registry_githandler
into ** on stacklok:main**.

[codecov]

Codecov Report

❌ Patch coverage is 72.32472% with 75 lines in your changes missing coverage. Please review.
✅ Project coverage is 47.38%. Comparing base (8f1a7e9) to head (7178bf0).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
cmd/thv-operator/pkg/git/client.go	65.55%	21 Missing and 10 partials ⚠️
cmd/thv-operator/pkg/sources/git.go	81.81%	22 Missing and 8 partials ⚠️
...thv-operator/api/v1alpha1/zz_generated.deepcopy.go	0.00%	14 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1925      +/-   ##
==========================================
+ Coverage   47.11%   47.38%   +0.26%     
==========================================
  Files         231      233       +2     
  Lines       28378    28649     +271     
==========================================
+ Hits        13369    13574     +205     
- Misses      14011    14061      +50     
- Partials      998     1014      +16     

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[Copilot]

Pull Request Overview

This PR introduces Git repository support for MCPRegistry sources, allowing registry data to be fetched directly from Git repositories instead of just ConfigMaps. This expands the flexibility of the registry system by enabling declarative management of MCP server registries through Git.

Key changes:

• Added Git source handler with support for branch, tag, and commit-based checkouts
• Implemented comprehensive Git client using go-git library
• Extended MCPRegistry CRD with Git source configuration

Reviewed Changes

Copilot reviewed 20 out of 21 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
go.mod	Adds go-git dependency and related Git operation libraries
cmd/thv-operator/api/v1alpha1/mcpregistry_types.go	Extends MCPRegistry CRD with GitSource type and validation
cmd/thv-operator/pkg/sources/git.go	Implements Git source handler for fetching registry data from repositories
cmd/thv-operator/pkg/git/client.go	Core Git client implementation with clone, checkout, and file operations
deploy/charts/operator-crds/templates/toolhive.stacklok.dev_mcpregistries.yaml	Updates CRD schema to include Git source configuration
examples/operator/mcp-registries/*.yaml	Provides example configurations for Git-based registry sources

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[jhrozek]

Mostly looks good, some questions about performance, most can be deferred but should be at least tracked.

[jhrozek]

Looks good once we fix the lint issues!