docs/language: a page for every keyword and attribute the vocabulary has

Keywords: module uses friend export internal numbers unsafe mut port bind action
reducer registry of as from def open alias component prop view (structure),
shows lasts then loads (scenes), system (ecs), dispatch (control), true false
null (operators). Attributes: @Ref @OneOf @Range @Unit @Asset @Color, @Node /
@Clip / @Material, @Tint @Derived, @Text / @Multiline, @Key, @AppendOnly /
@ByKey, @PerMap / @Chunked, @frame @max, @owns / @creates / @releases,
@deterministic @alloc_ok. Each is in tools/docgen/inventory.json; every fence
that is not marked skip parses (ludicc --fmt). annot-clearcolor's token loses its
quotes, which no reader strips.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/language/structure/kw-prop.md

@@ -0,0 +1,12 @@
+---
+id: kw-prop
+name: prop
+category: structure
+kind: keyword
+tokens: prop
+sig: component Name { prop name: Type = default }
+tip: A component's value handed in by its parent.
+order: 71
+---
+
+<code>prop</code> declares a component member its parent sets from the template (<code>&lt;Counter step="2"/&gt;</code>); <code>state</code> declares one the component keeps for itself. Both are fields of the instance, listed with their types and defaults in <code>ludic schema</code>.