deps: replace psycopg2-binary with psycopg2

[PeakPy]

This PR addresses the PostgreSQL dependency part of issue #248 by replacing psycopg2-binary with the recommended psycopg2 package.

Changes:

• Remove psycopg2-binary from project dependencies in pyproject.toml.
• Add psycopg2>=2.9.9 as the production-safe PostgreSQL driver.
• Update uv.lock accordingly.

Rationale:

• psycopg2-binary is not recommended for production use.
• The project already uses asyncpg for async access; psycopg2 is only needed for sync tooling (e.g. tests, create_engine).

Tests:

• uv run pytest
• uv run ruff check src
• uv run mypy src

[LucasQR]

psycopg2-binary is a dev-only dependency — it's listed under [project.optional-dependencies] dev in pyproject.toml, not in the main dependencies. It is not
installed in production.

It's needed because the test suite (tests/conftest.py) uses a synchronous SQLAlchemy engine (create_engine with the postgresql:// prefix), which requires a sync
PostgreSQL driver. asyncpg only works with async engines (postgresql+asyncpg://) and cannot serve this role.

The production application uses exclusively asyncpg for all database access. The -binary variant is appropriate here since it's only used in dev/CI environments
where ease of installation matters more than building from source.