Fix Core update discovery for mixed flat and versioned module installations #2

Problem

Gerber /update reports Unavailable even though PSGallery contains Gerber 0.1.0, matching the installed version.

The investigated installation contains both a numeric version directory and a legacy flat module layout. PSModuleUpdate interprets resource directories such as en-US and resources as installed-version candidates and raises PMU.ModuleIdentityMismatch before repository discovery. Gerber consequently displays generic repository/connectivity guidance.

Expected behavior

Valid mixed installation layouts must not prevent discovery. Installed and available Gerber 0.1.0 must produce UpToDate, show the available version, and offer no installation.

Scope

• Correct installation-candidate classification in PSModuleUpdate.
• Preserve supported flat/versioned layouts and existing identity validation.
• Add an upstream regression test before implementing the fix.
• Require the corrected PMU release from Gerber.
• Verify Gerber’s built-module integration and terminal presentation.
• Update stale publication statements and relevant release documentation.

Acceptance criteria

• Reproduce the failure with a disposable mixed-layout fixture before implementation.
• Ignore ordinary resource directories without suppressing genuine installation-identity errors.
• Show installed 0.1.0, available 0.1.0, and UpToDate, without installation consent.
• Preserve newer-stable eligibility and fail-closed repository behavior.
• Keep discovery read-only and retain Gerber’s PSGallery-only Stable/CurrentUser policy.
• Record focused before/after test evidence and pass required unit, integration, analyzer and PTY gates.
• Document dependency delivery/bootstrap requirements without modifying existing user installations automatically.

Implementation notes

PMU remains the sole discovery and version-selection authority. Do not add a second PSGallery query, error-text heuristics, or custom version comparisons in Gerber.

Complete the upstream fix before integrating its release into Gerber. Confirm authoritative PMU source paths and validation commands before editing.

Out of scope

Plugin updates, alternative repositories, automatic installation cleanup, unrelated provider-error classification, and release execution.

Open questions

• Confirm the authoritative PSModuleUpdate checkout and corrected release version.
• Confirm whether the originally reported environment matches the investigated profile.

Current evidence

Read-only investigation reproduced the local PMU identity error and confirmed Gerber 0.1.0 exists in PSGallery. No implementation, regression suite, or installation qualification has been completed.