Add R/Python defined as Bash alias when looking for binaries

System details:

Ubuntu 24.04

Positron and OS details:

Positron Version: 2025.02.0 build 171
Code - OSS Version: 1.96.0
Commit: 55f73310e900d46f5f472b4b7e2baa552aa2f157
Date: 2025-02-10T15:48:36.459Z
Electron: 32.2.6
Chromium: 128.0.6613.186
Node.js: 20.18.1
V8: 12.8.374.38-electron.0
OS: Linux x64 6.8.0-54-generic

Interpreter details:

R 4.4.2

Describe the issue:

I have R built as a Singularity container, so I can use the exact same R locally or in a cluster environment. When Positron starts and looks for R/Python binaries, it does not find my local R, presumably because it is defined as a Bash alias rather than a binary in the $PATH.

Steps to reproduce the issue:

1. Download our R Singularity build script here: https://raw.githubusercontent.com/accre/singularity/refs/heads/master/accre-internal/Singularity.R-4.4.2
2. Build a Singularity container with it: sudo singularity build R-4.4.2.sif Singularity.R-4.4.2
3. Add a Bash alias to start R: alias R="singularity run ~/sif/R/R-4.4.2.sif /usr/local/bin/R"
4. Start Positron. It does not detect my R and add it to the "Start Interpreter" selector.

On Bash, you could use a one-liner to detect R/Python binaries defined as aliases:

# alias | grep -E "alias (R|python)="
alias R='singularity run ~/R-4.4.2-x86-64-v3.sif /usr/local/bin/R'

Expected or desired behavior:

Positron detects my R and puts it under the "Start Interpreter" selector.

Were there any error messages in the UI, Output panel, or Developer Tools console?

Start at the interpreter discovery flow behind the Start Interpreter selector and reproduce the issue on Ubuntu with the R Singularity build and Bash alias described above. Trace how available R/Python interpreters are found, then verify that an alias-backed interpreter is detected and selectable without regressing ordinary PATH-based discovery.