Implement pathOf function for extracting property paths from lambda expressions

[Copilot]

This PR implements a new pathOf function that extracts property paths from lambda expressions, similar to the C# ExpressionUtils.PathOf functionality.

Features

The pathOf function takes a lambda expression and returns the property path as a string:

import { pathOf } from '@neolution-ch/javascript-utils';

// Simple property access
pathOf(x => x.prop); // Returns "prop"

// Nested property access
pathOf(x => x.nested.value); // Returns "nested.value"

// Deep nesting (matching the C# example)
pathOf(x => x.Recursion.Recursion.Recursion.Recursion); // Returns "Recursion.Recursion.Recursion.Recursion"

Implementation

The function uses JavaScript Proxy to intercept property access and build the path string:

• Type-safe: Uses TypeScript generics with proper object constraints
• Robust: Handles runtime errors gracefully with try-catch
• Efficient: Uses a proxy-based approach to track property access without executing the actual expression
• Well-documented: Includes comprehensive JSDoc documentation

Testing

Added 8 comprehensive test cases covering:

• Simple property access
• Nested property access
• Deep property nesting
• Different property types
• Edge cases and error handling

All existing tests continue to pass (412 tests total), ensuring no regressions.

Code Quality

• ✅ Passes all linting rules
• ✅ Builds successfully
• ✅ Follows prettier formatting
• ✅ 96% code coverage (catch block safety net not covered, which is expected)

Fixes #14.

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[manni497]

@copilot I think you run the wrong command to install package depencies. Please undo this and package-lock.json and use 'yarn' instead of 'npm install' to install your dependencies

[Copilot]

Fixed! I've removed the package-lock.json file and restored yarn.lock to its original state, then used yarn to install dependencies. Commit e47fb70 addresses this issue.