Add description and tags to Vue route definitions

### Description

Vue routes currently have no metadata that helps LLMs reason about which route to pick. Adding `description` and `section` keys to each route's `meta` gives MCP clients the context they need to make better navigation decisions.

`section` is a single required value from a fixed, closed set (one per feature area: application, instance, device, team, broker, pipeline, library, tables, account, admin, general) rather than free-form tags, since it's also the value `ui_list_routes` filters on directly (see #7934, the section-scoped listing issue).

This is the least intrusive step toward making routes proper MCP resources, and it doesn't change any existing functionality.

### Epic/Story
Part of #7920

### Have you provided an initial effort estimate for this issue?
I have provided an initial effort estimate

Search the Vue application for route definitions and inspect how ui_list_routes consumes route metadata, using #7934 for the section-filtering context. Add the required description and one allowed section value to each route's meta, then verify all routes are covered and existing functionality remains unchanged.

Written by the indexing model from the issue text.