Add escapeBreakLine utility and tests for special character handling

[raulfdm]

Closes #162

This pull request improves the handling of slot values in the @layerfig/config package, especially for multiline and special-character-containing strings. The main change is the introduction of a utility to safely escape line breaks and special characters before slot value insertion, preventing misparsing and rendering issues. Additionally, tests have been added to ensure correct escaping, and the slot replacement logic in sources has been updated accordingly.

Escaping and slot value handling:

• Added a new utility function escapeBreakLine to escape backslashes, double quotes, newlines, carriage returns, and tabs in slot values before insertion, preventing parsing and rendering errors. (packages/config/src/utils/escape-break-line.ts, packages/config/src/utils/escape-break-line.tsR1-R12)
• Updated slot replacement logic in Source to use escapeBreakLine when inserting slot values, and refactored parsing to use JSON.parse directly for consistency. (packages/config/src/sources/source.ts, [1] [2] [3]

Testing improvements:

• Added comprehensive unit tests for escapeBreakLine, covering all relevant escape scenarios including multiline PEM keys and combinations of special characters. (packages/config/src/utils/escape-break-line.test.ts, packages/config/src/utils/escape-break-line.test.tsR1-R74)
• Added a test to ensure that multiline slot values (such as PEM keys) are correctly handled and preserved in the final configuration. (packages/config/src/config-builder.test.ts, packages/config/src/config-builder.test.tsR202-R226)

Documentation and changelog:

• Added a changeset documenting the fix for escaping line breaks and special characters in slot values. (.changeset/tasty-baboons-run.md, .changeset/tasty-baboons-run.mdR1-R7)

[changeset-bot]

🦋 Changeset detected

Latest commit: 57a88c3

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@layerfig/config	Patch

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Status	Name	Latest Commit	Preview URL	Updated (UTC)
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