chore: bump version to 2.1.0

[JeanExtreme002]

Bumps __version__ from 2.0.1 to 2.1.0.

The last bump was in 9a0b41e (tag v2.0.1). Since then, four commits landed on main without a version bump:

Commit	Change
4aef4c2	feat: add read_process_memory_into for zero-copy buffer reuse (#71) (#72)
041bfc0	ci: remove macOS from the CI matrix
a2c583b	fix(app): prevent OverflowError from addresses above 2^63 in memory map (#77)
b656c55	fix(app): handle SIGINT so the app can close from a terminal (#78)

read_process_memory_into is a new public API, so this is a minor bump rather than a patch.

pyproject.toml reads the version from PyMemoryEditor/__init__.py via [tool.hatch.version], so no other file needs updating.