The authoritative list of Raxol's first-class UI components.

What this IS

One entry per component that is reachable as a declaration type -- an atom the layout engine dispatches on, that Raxol.MCP.TreeWalker can derive agent tools from, and that Raxol.Core.Accessibility.Projection can project into an accessibility node. Each entry records the type atom, the implementing module, a group (drawn from the Raxol.Playground.Catalog category vocabulary), which of the two cross-cutting behaviours the module actually implements, and the name of the Catalog demo that shows it off (nil where none exists yet).

What this IS NOT

It is not an index of every module under Raxol.UI.* -- there are ~94, and most are internal sub-modules of a component (SelectList.Renderer, Table.State) or non-declarative helpers with no type atom of their own. A registry that listed them would be noise: nothing dispatches on them, so nothing can drift from them.

It is also not the playground catalog. Raxol.Playground.Catalog is a list of runnable examples (42 of them, keyed by demo module); several demos hand-roll their subject with the View DSL, and several components here have no demo at all. The :demo field is the join between the two, not a duplication.

Why the package-side maps still exist

Raxol.MCP.TreeWalker and Raxol.Core.Accessibility.Projection each carry their own type -> module map. They live in raxol_mcp and raxol_core, neither of which depends on main raxol, so they cannot read this module at compile time -- they cannot even name a component module without a @compile {:no_warn_undefined, ...} escape, and resolve modules at runtime behind a function_exported?/3 guard. Deriving those maps from this registry would invert the dependency direction of the umbrella.

The maps are therefore duplicated on purpose and kept honest by test: Raxol.UI.RegistryConformanceTest runs in the main app (where every component module is loaded) and fails when a map and this registry disagree, or when an entry claims a behaviour its module does not implement.