everything: gzip-file-as-resource's generated resource carries no icons in either era #5434

Problem

#3131 gave every everything primitive light and dark icons, and the docs now say so: docs/features.md ("every entry of tools/list, prompts/list, resources/list and resources/templates/list carry an icons array") and the README ("every tool, prompt, resource and resource template carry a pair of icons").

gzip-file-as-resource with outputType: "resourceLink" (the default) creates a resource with no icons, in both eras:

• 2025-era client: the tool registers a session resource (resources/session.ts, registerSessionResource). That function passes along whatever icons the resource object carries, and tools/gzip-file-as-resource.ts sets none. The new entry appears in resources/list with no icons, and so does the returned resource_link.
• 2026-07-28 client: the minted resource link (resources/minted.ts, the resource_link the mint function returns) has no icons, though the minted-resource template does (RESOURCE_TEMPLATE_ICONS).

Copilot found it reviewing the milestone merge PR #5430 for the v2.3.0 release (#5425). It is part of what #3131 shipped in this milestone, so it is fixed before release.

Expected

The generated resource carries RESOURCE_ICONS (server/icons.ts) in both places: the 2025-era session resource (so its resources/list entry and its link have them) and the 2026-07-28 minted link. The icon tests (__tests__/icons.test.ts) exercise both paths.