fix: the usage of path.join

[shyim]

No description provided.

[Copilot]

Pull request overview

This PR fixes path handling issues by replacing the path package with path/filepath for filesystem operations and corrects several related issues.

Changes:

• Replaced path import with path/filepath in platform.go and bundle.go for proper cross-platform path handling
• Fixed a bug where defaultNotAllowedPaths global slice was being mutated by using slices.Clone
• Replaced string concatenation with filepath.Join for path construction in zip.go
• Changed context.Background() to use the provided ctx parameter in GetPhpVersion function
• Corrected error message from "manifest.xml" to "composer.json" in build_modifier.go

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
internal/extension/zip.go	Fixed global slice mutation bug using slices.Clone; replaced string concatenation with filepath.Join for path construction
internal/extension/platform.go	Replaced path package with path/filepath for filesystem operations; fixed context usage in GetPhpVersion
internal/extension/bundle.go	Replaced path package with path/filepath for filesystem operations
internal/extension/build_modifier.go	Fixed error message typo (manifest.xml → composer.json)

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