Summary
Fixes syntax errors in remote module transformation when .remote.js files end without a trailing semicolon, space, or newline.
Fixes #14726

Problem
Remote module transformation fails with syntax errors when the source file ends with an expression or a comment and lacks a trailing semicolon, space, or newline.
This causes the concatenated output to become invalid JavaScript.

Example of the Problem:

// Original file ends with:
console.log(22)

// Becomes invalid after transformation:
console.log(22)import * as $$_self_$$ from "./test.remote.js";
//                                    ^ Syntax error here

Root Cause
When Vite transforms .remote.js files, it concatenates the generated code directly with the original module.
If the original file ends with an expression (e.g. console.log) or a comment without a trailing newline, the combined code breaks syntax validity.

Fix
Ensure safe concatenation by adding a newline (or other delimiter) between the transformed code and the original module content.

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Tests

• Run the tests with pnpm test and lint the project with pnpm check
• Note: One intermittent timeout error in test suite (unrelated to string concatenation change)

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