feat: support non-root build paths

[txabman42]

Contributing to #196

Support building non-root paths e.g. otel go build -a ./app/vmctl

[codecov]

Codecov Report

❌ Patch coverage is 60.78431% with 20 lines in your changes missing coverage. Please review.
✅ Project coverage is 53.32%. Comparing base (3bd8623) to head (00d7c0d).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
tool/internal/setup/setup.go	53.48%	18 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #209      +/-   ##
==========================================
+ Coverage   51.22%   53.32%   +2.10%     
==========================================
  Files          48       48              
  Lines        3274     3306      +32     
==========================================
+ Hits         1677     1763      +86     
+ Misses       1477     1420      -57     
- Partials      120      123       +3     

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[txabman42]

Not sure that we want to have code coverage as required. I usually don't like to require that, even less if right now great part of our app is tested via integration/e2e tests.

[kakkoyun]

@y1yang0 Could you have another look at this?

[Copilot]

Pull request overview

This pull request adds support for building non-root package paths (e.g., otel go build -a ./app/vmctl) by implementing package discovery functionality. The implementation uses the golang.org/x/tools/go/packages library to correctly identify and process build targets from command-line arguments.

Key Changes

• Package Discovery: New GetBuildPackages function parses go build arguments to identify target packages, handling flags, multiple packages, and wildcard patterns
• Multi-package Support: The setup phase now generates otel.runtime.go files in each target package directory rather than only in the root
• Deterministic Imports: Import declarations in generated files are now sorted for consistent output

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
tool/util/go.go	Adds GetBuildPackages function to extract package patterns from build arguments and load corresponding packages
tool/util/go_test.go	Comprehensive tests for package discovery covering single/multiple packages, wildcards, flags, and edge cases
tool/internal/setup/setup.go	Integrates package discovery to generate instrumentation files in each target package directory and update cleanup logic
tool/internal/setup/add.go	Updates addDeps to accept package path parameter, adds deterministic import ordering, and improves logging
tool/internal/setup/add_test.go	Golden file tests for the addDeps function covering various rule configurations
tool/internal/setup/testdata/*.golden	Golden files for testing generated otel.runtime.go content
go.mod	Moves golang.org/x/tools from indirect to direct dependency

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[y1yang0]

I'll take a look tomorrow. Thanks

[y1yang0]

Otherwise LGTM