fix: avoid false positives in import cycle detection

[AustinAbro321]

Description

Replaces the map cycle detection with a stack-based approach. The current approach caused false positives if multiple components import the same sub-package in a specific directory hierarchy because filepath.Join will clean the path causing it to look like the same import is occurring multiple times. Another potential solution is to use os.PathSeparator instead of filepath.Join to avoid cleaned filepaths

This PR instead uses a stack and only checks the current chain of imports to avoid false positives.

Related Issue

Fixes #3448

Checklist before merging

• Test, docs, adr added or updated as needed
• Contributor Guide Steps followed

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[codecov]

Codecov Report

Attention: Patch coverage is 90.90909% with 1 line in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/internal/packager2/layout/import.go	90.00%	1 Missing ⚠️

Files with missing lines	Coverage Δ
src/internal/packager2/layout/create.go	31.47% <100.00%> (ø)
src/internal/packager2/layout/import.go	38.55% <90.00%> (+24.05%)	⬆️

[mkcp]

LGTM