fix(podman): resolve macOS Podman socket dynamically

[gmenher]

Summary

This PR removes the last macOS Podman socket assumption from the driver-config volume e2e path and makes the Podman-backed e2e harness respect the socket reported by podman machine inspect.

On newer macOS Podman setups, the legacy ~/.local/share/containers/podman/machine/podman.sock path is not a reliable source of truth after restarting podman machine. That meant the driver-config volume helper and the Podman e2e flow could fail even when the VM was healthy and reachable through the socket Podman itself reports.

Related Issue

Closes #1690

Changes

• Prefer OPENSHELL_PODMAN_SOCKET when it is already set, so explicit user overrides still win.
• On macOS, resolve the Podman API socket from podman machine inspect before falling back to the legacy socket path.
• Export CONTAINER_HOST whenever the Podman socket is resolved so child processes and follow-on commands use the same endpoint.
• Make the Podman e2e preflight use the resolved socket consistently instead of assuming the legacy socket layout.
• Add focused tests for parsing macOS podman machine inspect output.
• Tighten a couple of Bash array expansions in the e2e and prebuilt-binary scripts so empty-array cases stay safe.

Testing

• mise run pre-commit passes
• Unit tests added/updated
• E2E coverage updated and validated for the Podman lane
• Manual smoke test after restarting podman machine confirmed the full user flow

Checklist

• Follows Conventional Commits

[copy-pr-bot]

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[github-actions]

All contributors have signed the DCO ✍️ ✅
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[gmenher]

I have read the DCO document and I hereby sign the DCO.

[johntmyers]

gator-agent

PR Review Status

The macOS Podman fix is project-valid and the focused socket changes are ready to continue, but the latest commit also removes a repository-advertised troubleshooting skill while leaving its callers and documentation intact.

Action required: restore .agents/skills/debug-openshell-cluster/SKILL.md, or move an intentional coordinated removal into a complete, separately scoped change.

Blocking findings:

• GATOR-b92131c8-01: the deleted skill remains referenced by repository guidance and companion workflows.

Carried findings:

• None

Gator metadata

• Validation: Concentrated macOS Podman compatibility fix linked to triaged issue #1690
• Docs: Fern compute-driver reference updated; existing reference-folder navigation covers the page
• Checks: Current-head branch and Helm gates are waiting for the copy-PR mirror
• E2E: Required for Podman runtime behavior; dispatch deferred until blocking review feedback is resolved
• Head SHA: b92131c8a572bf935fd60a0f2784116b823ec676
• Base SHA: 8bc79552638a625971f8c6d30c26efa917a19cf9
• Merge base SHA: 06f0aa6fe30177f2aecba9af396649adae4d7cdd
• Patch ID: 4bae9c48f63693d1ea65d2a789486c786b681b6d
• Gator payload: 8
• Review mode: initial
• Previous reviewed SHA: none
• Review budget exhausted: no
• Maintainer decision required: no
• Next state: gator:in-review

[github-actions]

Label test:e2e applied, but pull-request/3135 does not exist yet. A maintainer needs to comment /ok to test 69bf396d84f2b52f2b96b5c4e24e237211913560 to mirror this PR. Once the mirror exists, re-apply the label or re-run Branch E2E Checks from the Actions tab.

[johntmyers]

/ok to test 69bf396

[johntmyers]

gator-agent

PR Review Status

The author-only follow-up resolves GATOR-b92131c8-01: the effective PR tree keeps the canonical public troubleshooting skill and applies the intended macOS Podman guidance there. The bounded delta review found no new blocking findings, and the required Branch Checks, Helm Lint, and E2E workflows are queued for the current head.

Blocking findings:

• No blocking findings remain

Carried findings:

• None; GATOR-b92131c8-01 is resolved

Gator metadata

• Validation: Concentrated macOS Podman compatibility fix linked to triaged issue #1690
• Docs: Fern compute-driver reference and canonical public troubleshooting skill are updated; existing reference navigation covers the page
• Checks: Current-head Branch Checks and Helm Lint workflows are queued
• E2E: test:e2e applied; /ok to test 69bf396d84f2b52f2b96b5c4e24e237211913560 posted; current-head Branch E2E workflow is queued
• Head SHA: 69bf396d84f2b52f2b96b5c4e24e237211913560
• Base SHA: 8bc79552638a625971f8c6d30c26efa917a19cf9
• Merge base SHA: 06f0aa6fe30177f2aecba9af396649adae4d7cdd
• Patch ID: a80112376cbab89bacc549dc61b77904c9dfd8ba
• Gator payload: 8
• Review mode: follow_up
• Previous reviewed SHA: b92131c8a572bf935fd60a0f2784116b823ec676
• Review budget exhausted: no
• Maintainer decision required: no
• Next state: gator:watch-pipeline