bug(install): install.sh prints gawk "escape sequence \. treated as plain ." warnings on RPM hosts #4768

User Story

I use OpenShell (0.1.3, checked against 0.1.5) on RHEL 9, and I install it with the published install.sh. Each RPM install prints three gawk warnings in the middle of the installer output. Users ask whether the install failed.

Problem Statement

find_rpm_asset builds its fallback regexes as "^openshell-[0-9].*\\.${_arch}\\.rpm$" (and the same for the gateway and prover packages). It passes them to awk with -v fallback_re=.... awk processes escape sequences in -v values, so the \. reaches awk as an escape:

• gawk warns escape sequence '\.' treated as plain '.' once per regex.
• The dot then matches any character instead of a literal dot.

Impact / Why This Matters

• Every RPM install shows three warnings that look like errors.
• The fallback match is looser than intended.
• There is no workaround for users of the published script. A wrapper that pins the script by digest cannot change it.

Acceptance Criteria

• An RPM install on RHEL 9 (gawk) prints no awk warnings.
• The fallback regex matches a literal . before the arch and before rpm.
• tasks/scripts/test-install-sh.sh covers find_rpm_asset under gawk and fails on any stderr output.

Reproduction Steps

1. On RHEL 9, run curl -fsSL https://raw.githubusercontent.com/NVIDIA/OpenShell/v0.1.5/install.sh | sh (RPM path).

Expected: no awk warnings.
Actual: three gawk warnings.

Suggested UX (if applicable)

None.

Environment

• OpenShell install.sh and checksum-verified RPM packages from v0.1.5.
• RHEL 9.8 UBI RPM container on a RHEL 9.8 host, kernel 5.14.0-687.45.1.el9_8.x86_64; gawk 5.1.0; Docker 29.8.1; Podman 5.8.2. Host KVM was present but not used for this installer repro.

Logs

awk: warning: escape sequence `\.' treated as plain `.'
awk: warning: escape sequence `\.' treated as plain `.'
awk: warning: escape sequence `\.' treated as plain `.'
openshell: installed openshell RPM packages from v0.1.5