ƒeat: dev deps support

[pedrosousa13]

No description provided.

[Copilot]

Pull request overview

Adds improved support for dev dependencies when running lnpm add, including preserving devDependencies placement for packages that are already listed there.

Changes:

• Update updatePackageJSON to select devDependencies when appropriate and remove duplicate entries across dependency fields.
• Add a regression test ensuring lnpm add (and no --dev) keeps an existing dev dependency in devDependencies.
• Adjust progress-line clearing spacing in pack/store workflows.

Reviewed changes

Copilot reviewed 2 out of 4 changed files in this pull request and generated 2 comments.

File	Description
tests/add_test.go	Adds coverage for preserving devDependencies location when re-adding without --dev.
internal/cli/add.go	Implements dependency-field selection logic and de-duplication when updating package.json.
internal/store/store.go	Tweaks console progress-line clearing width after large operations.
internal/pack/pack.go	Tweaks console progress-line clearing width after large scans.

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[Copilot]

The test ignores the error from json.Unmarshal and then does an unchecked type assertion on result["devDependencies"]. If package.json can't be read/parsed, this can panic and obscure the real failure. Please check the ReadFile/Unmarshal errors and guard the type assertion (or reuse the existing helper accessors used elsewhere in tests).

Suggested change

	data, _ = os.ReadFile(pkgJSONPath)
	var result map[string]interface{}
	json.Unmarshal(data, &result)
	deps := result["dependencies"]
	devDeps := result["devDependencies"].(map[string]interface{})
	data, err := os.ReadFile(pkgJSONPath)
	if err != nil {
	t.Fatalf("Failed to read package.json: %v", err)
	}
	var result map[string]interface{}
	if err := json.Unmarshal(data, &result); err != nil {
	t.Fatalf("Failed to unmarshal package.json: %v", err)
	}
	deps := result["dependencies"]
	devDepsVal, ok := result["devDependencies"]
	if !ok {
	t.Fatalf("package.json missing devDependencies field")
	}
	devDeps, ok := devDepsVal.(map[string]interface{})
	if !ok {
	t.Fatalf("devDependencies has unexpected type: %T", devDepsVal)
	}

[Copilot]

The comment says “if package exists in devDependencies: use devDependencies (preserve location)”, but the condition only preserves devDependencies when the package is NOT also in dependencies (!inDeps && inDevDeps). Either adjust the condition to match the documented behavior, or update the comment to reflect the actual precedence when a package appears in both fields.

Suggested change

	// - Else if package exists in devDependencies: use devDependencies (preserve location)
	// - Else if package exists only in devDependencies (and not in dependencies): use devDependencies