This change makes memfs behavior consistent with Node.js on Linux by throwing ENOTDIR when attempting to read a file using a path with a trailing slash.

Problem

Previously, memfs would successfully read a file even when accessed with a trailing slash:

const { fs } = require('memfs');
fs.writeFileSync('/foo', 'hello');
console.log(fs.readFileSync('/foo/', 'utf8')); // Returns 'hello' (incorrect)

However, native Node.js on Linux throws an ENOTDIR error in this case:

const fs = require('node:fs');
fs.writeFileSync('/foo', 'hello');
console.log(fs.readFileSync('/foo/', 'utf8')); // Throws ENOTDIR (correct)

Solution

Modified the _readfile method in src/node/volume.ts to:

1. Detect when the original path has a trailing slash before normalization
2. Check if the resolved path points to a file (not a directory)
3. Throw ENOTDIR error when trying to read a file with a trailing slash

The fix preserves existing behavior for directories and handles edge cases like symlinks, multiple trailing slashes, and the root path correctly.

Testing

Added comprehensive test cases covering:

• Files with and without trailing slashes
• Directories with and without trailing slashes
• Symlinks to files with trailing slashes
• Edge cases like root path and multiple slashes

All existing tests continue to pass, ensuring backward compatibility.

Fixes #1051.

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