fix(63726): fix declaration emit for multiline jsdoc literal types

[Oleksandr Tarasiuk (a-tarasyuk)]

Fixes microsoft/TypeScript#63726

[Copilot]

Pull request overview

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Adds a regression test and adjusts scanner trivia-skipping to correctly preserve multiline JSDoc literal union types during declaration emit (fixes TypeScript issue #63726).

Changes:

• Added a new compiler test case for multiline JSDoc union literal typedefs in JS files.
• Updated the reference baseline to validate correct .d.ts output and preserved JSDoc formatting.
• Adjusted GetTextOfNodeFromSourceText to use JSDoc-aware trivia skipping when extracting text from JSDoc nodes.

Reviewed changes

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

File	Description
testdata/tests/cases/compiler/jsdocMultilineUnion.ts	New regression test covering multiline JSDoc literal union typedef formatting.
testdata/baselines/reference/compiler/jsdocMultilineUnion.js	Baseline validating correct declaration emit and preserved multiline JSDoc formatting.
internal/scanner/utilities.go	Uses JSDoc-aware trivia skipping when extracting node text for JSDoc nodes.