Bump GLQL packages and document multi-group/project scope

Goal

Ship multi-group and multi-project scope (group in (...) / project in (...) in analytics mode) to GitLab: bump the compiler packages to the release that contains both compiler MRs, and document the feature in the same MR. Part of &23512.

Bump

• Bump gitlab_query_language (Gemfile) and @gitlab/query-language-rust (package.json) to the release cut after glql!497 (merged) and glql!498 (merged) have both merged. They must land in the same release: on the compile MR alone an organization-rooted response fails at transform.
• Nothing else is needed on the GitLab side: the feature is query syntax, so every consumer (markdown, wikis, dashboard panel YAML, /api/v4/glql and the Data Analyst Agent) gets it with the bump. Both /api/glql and /api/v4/glql execute the compiled GraphQL as is and already set the current organization.

Docs (doc/user/glql/)

• group and project accept a list in analytics mode: group in ("gitlab-org", "gitlab-com"), project in ("a/x", "b/y"), and group = "a" and project in ("a/x", "a/y") (projects under one group). Groups and projects listed together are a union.
• Requires GitLab 19.3 or later. Pattern to follow: the pipelines analytics page states its 19.2 minimum.
• Limits: at most 20 groups and projects combined; paths are deduplicated case-insensitively; a list of one path behaves like =.
• Standard mode (issues, merge requests, ...) keeps taking a single group or project; a list there is a compile error.
• Access: every listed group or project is checked individually; one you cannot read fails the whole query with The following sources are not accessible: <paths>.
• Per-source pages: each analytics source page's "Allowed scopes" section gains the list forms (all analytics sources support them).

Source of truth for the rules: glql#151 (closed) and the MR descriptions; backend contract in #600674 (closed).

Not here

Wiring the dashboard group/project filters into group in (...) is control wiring, tracked under &22615 / glql#154.