uv tool run error messages references uvx when appropriate

[blueraft]

Summary

Resolves #5013.

Test Plan

❯ ./target/debug/uv tool run fastapi-cli
warning: `uv tool run` is experimental and may change without warning.
Resolved 9 packages in 28ms
The executable fastapi-cli was not found.
However, the following executables are available via uv tool run --from fastapi-cli <EXECUTABLE>:
- fastapi

❯ ./target/debug/uvx fastapi-cli
warning: `uvx` is experimental and may change without warning.
Resolved 9 packages in 23ms
The executable fastapi-cli was not found.
However, the following executables are available via uvx --from fastapi-cli <EXECUTABLE>:
- fastapi

[charliermarsh]

Thanks so much, that was so fast!