feat: add IsUvProject for uv project detection

[mcombuechen]

What this does

Exposes the uv lofile detection and FF check, so we can consume this in cli-extension-os-flows and don't have to leave the low-level, uv-specific code there. Addendum to #165.

[snyk-io]

✅ Snyk checks have passed. No issues have been found so far.

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[snyk-pr-review-bot]

PR Reviewer Guide 🔍

🧪 PR contains tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Logging Regression 🟠 [major] The IsUvProject function hardcodes a nil logger when calling HasLockFile. In the previous implementation within callback.go (see old hunk), HasLockFile was passed a valid *zerolog.Logger. This change silences diagnostic logs during the project detection phase, which are critical for debugging why a project might be skipped (e.g., permission issues or path mismatches). Furthermore, if HasLockFile is not defensive against nil loggers, this will cause a panic at runtime. if !HasLockFile(dir, targetFile, allProjects, nil) { Brittle Test Constant 🟡 [minor] The test defines a local constant featureFlagUvCLI with a hardcoded string value instead of importing and using workflow.FeatureFlagUvCLI from internal/workflow. Since detection.go relies on the internal/workflow constant, any future change to that constant's value would result in tests passing while the production code fails to detect the flag correctly. const featureFlagUvCLI = "internal_snyk_cli_uv_enabled"

📚 Repository Context Analyzed This review considered 7 relevant code sections from 7 files (average relevance: 0.91) pkg/ecosystems/python/uv/uvclient.go (lines 1-203) pkg/ecosystems/python/uv/plugin.go (lines 1-259) pkg/depgraph/sbom_resolution.go (lines 1-225) internal/legacycli/legacy_resolution.go (lines 1-97) pkg/ecosystems/legacy/plugin.go (lines 1-205) pkg/depgraph/callback.go (lines 1-49) pkg/ecosystems/python/uv/detection.go (lines 1-22)