Fix: Use SHA256 hash for registry keys related to file paths

[seer-by-sentry]

Resolved / Related Issues

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• Closes FILES-APP-37R

Steps used to test these changes

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1. The issue was that: Registry key creation fails because LayoutPreferencesDatabase.FindPreferences uses excessively long file paths directly as registry key components, exceeding the 255-character limit.
2. Introduces a CreateSHA256 method in ChecksumHelpers.cs to generate SHA256 hashes from strings.
3. Modified LayoutPreferencesDatabase.cs and FileTagsDatabase.cs to use SHA256 hashes of file paths as registry keys instead of the file paths themselves.
4. This change aims to improve security and prevent potential issues with special characters or excessively long file paths in registry keys.
5. Verified fix for FILES-APP-37R.

[Copilot]

Pull Request Overview

This PR refactors the registry key creation mechanism to use SHA256 hashes of file paths instead of the raw file paths themselves. This addresses issues with registry key creation failures when file paths exceed the 255-character limit and improves security by avoiding potential issues with special characters in file paths.

• Adds a new CreateSHA256 method to generate SHA256 hashes from input strings
• Updates FileTagsDatabase to use SHA256 hashes of file paths as registry keys
• Updates LayoutPreferencesDatabase to use SHA256 hashes of file paths as registry keys

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/Files.Shared/Helpers/ChecksumHelpers.cs	Adds new CreateSHA256 method for generating SHA256 hashes from strings
src/Files.App/Utils/FileTags/FileTagsDatabase.cs	Replaces direct file path usage with SHA256 hashes in registry key creation
src/Files.App/Helpers/Layout/LayoutPreferencesDatabase.cs	Replaces direct file path usage with SHA256 hashes in registry key creation

Comments suppressed due to low confidence (1)

src/Files.Shared/Helpers/ChecksumHelpers.cs:25

• [nitpick] The method name 'CreateSHA256' is ambiguous. Consider renaming it to 'CreateSHA256Hash' or 'ComputeSHA256Hash' to clearly indicate that it computes a hash value.

		public static string CreateSHA256(string input)

[hishitetsu]

I'm amazed that AI came up with this way of fix.
But this will invalidate the old registry keys, so we will need to consider migrating them.

[yaira2]

Merging with #17389