Add height and weight filters to player directory interface

[6qdbq9nf8w-cmd]

Summary

Add UI controls and filtering logic to allow users to filter NBA players by height and weight in the Streamlit interface.

Background / Motivation

Currently, users can filter by name, team, school, country, position, and draft year. Adding height and weight filters will help users find players that meet specific physical criteria.

Requirements / Acceptance Criteria

Add UI controls (min/max or range sliders) for height and weight in the sidebar.
Filtering should update the displayed player list immediately.
The result list must only include players whose height and weight fall within the specified ranges (inclusive).
Clearly indicate units (e.g., inches for height, pounds for weight) in the UI.
Handle edge cases: empty or invalid inputs, min > max (show validation), and missing data for some players (treat as excluded or provide an option to include).
Implementation Notes

Inspect nba-mock-data/players.csv to confirm column names and units for height and weight.
Implement filtering client-side, as the app loads the CSV into memory.
Add validation and unit labels in the UI.
Update README or docs with the new filter usage.
Tasks

Confirm column names and units for height and weight.

Add UI controls for height and weight filtering.

Implement filtering logic.

Add validation and unit labels.

Update documentation.
This issue is based on the current code in app.py and the project structure.