Edit prediction does not distinguish between project contexts

[failable]

Summary

Edit prediction does not distinguish between project contexts. After editing Python project A, the prediction in Rust project B is pretty much affected by the context in project A.

Steps to trigger the problem:

1. Run uv init ppp to initialize a Python project.
2. Open main.py and write a [gcd](https://en.wikipedia.org/wiki/Greatest_common_divisor) function.
3. Run cargo new --lib rrr to initialize a Rust project.
4. Open lib.rs and input fn(space) .

Actual Behavior:

The edit prediction shows a gcd function in Rust.

Expected Behavior:

Edit prediction should distinguish between project contexts.

Zed Version and System Specs

Zed: v0.179.1 (Zed Preview)
OS: macOS 15.3.2
Memory: 64 GiB
Architecture: aarch64

[notpeter]

Yeah, it might make sense to include the current buffer language as additional context. Perhaps we can add some samples to the training set which improve this.