Fix: Resolve dependency conflict in Docker build

[sthasmn]

This PR fixes a dependency conflict that prevents the Dockerfile from building a working image.

The Problem

The previous installation process installed torch and whisperlivekit in separate steps. This caused pip's dependency resolver to incorrectly handle a version conflict between torch (which requires triton>=3.0) and whisperlivekit (which requires triton<3.0).

The result was a silent downgrade of torch, leading to a container that would crash on startup with an OSError: undefined symbol in torchaudio.

The Solution

This change resolves the issue by:

1. Combining the Python package installations into a single, unified RUN command.
2. Using --extra-index-url instead of --index-url to ensure pip can access both the main PyPI repository and the special PyTorch index.

This allows pip to see all dependency constraints at once and install a consistent, compatible set of packages, resulting in a successful build and a working container.

[CoderRahul9904]

@sthasmn resolve the conflict add screenshot of proof !!!!