fix(tests): migrate expect assertion messages to Vitest format

[Copilot]

Vitest requires assertion messages as the second argument to expect(), not as the last argument to matchers like Jasmine.

Changes

• Migrated 421 assertion messages across 35 spec files
• Excluded toHaveBeenCalledWith from transformation (all arguments are call parameters)
• Handled both argument-taking matchers (toBe, toEqual) and no-arg matchers (toBeDefined, toBeTruthy)

Example

// Before (Jasmine)
expect(cells[0].value).toBe(147, 'wrong root level row');
expect(value).toBeDefined('should be defined');

// After (Vitest)
expect(cells[0].value, 'wrong root level row').toBe(147);
expect(value, 'should be defined').toBeDefined();

Implementation

Automated transformation using Python script that:

• Parses expect statements with proper handling of nested parentheses, brackets, and string literals
• Categorizes matchers by argument requirements
• Moves string literal messages from matcher args to expect() second parameter

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