refactor: Connect local execution helm configuration should not be coupled to the image's default connect configurations

❯ helm install rstudio/rstudio-connect --set launcher.enabled=false --set securityContext.privileged=true --generate-name
NAME: rstudio-connect-1772230278
LAST DEPLOYED: Fri Feb 27 17:11:18 2026
NAMESPACE: rsc-dev
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
rstudio-connect-1772230278 successfully deployed to namespace rsc-dev

helm on  main [$!]
❯ k get pods -w
NAME                                          READY   STATUS              RESTARTS   AGE
rstudio-connect-1772230278-67b46ccfc8-z4l2f   0/1     ContainerCreating   0          9s
run-python-application-r62zp-m6ph5            0/1     Completed           0          45m
rstudio-connect-1772230278-67b46ccfc8-z4l2f   0/1     Running             0          45s
rstudio-connect-1772230278-67b46ccfc8-z4l2f   0/1     Error               0          49s
rstudio-connect-1772230278-67b46ccfc8-z4l2f   0/1     Error               1 (5s ago)   50s
rstudio-connect-1772230278-67b46ccfc8-z4l2f   0/1     CrashLoopBackOff    1 (2s ago)   51s```

time="2026-02-27T22:13:21.202Z" level=error msg="Error: Python version specified at Python.Executable cannot be analyzed: /opt/python/3.11.13/bin/python: stat /opt/python/3.11.13/bin/python: no such file or directory"
time="2026-02-27T22:13:21.202Z" level=fatal msg="Error: Unable to configure execution environments: unable to initialize local environment: Unable to use Python on this system: Please fix the Python installation(s) above or remove them from the configuration file"

We have CI that is supposed to catch this but it appears it has been failing silently for a while now.

@aronatkins Maybe this is enough indication that we shouldn't be setting any default Executable in the helm configuration

A better approach might be to create a second configuration and overlay it on top of the image's default configuration with ./connect --config /etc/rstudio-connect/rstudio-connect.gcfg --config helm-generated.gcfg

Start by reproducing the helm install with launcher.enabled=false and inspecting the image's default configuration alongside helm-generated.gcfg. Trace how ./connect loads /etc/rstudio-connect/rstudio-connect.gcfg and helm-generated.gcfg, and review the CI check that should catch invalid Python.Executable values. Done means local execution no longer depends on image-specific default executables and the relevant CI validation detects configuration failures.