docs(api): per-symbol pages, fuzzy search, deep token linking, hover cards

Rebuild the API Reference around one page per symbol and richer, verified content.

Pages & navigation
- One HTML page per symbol (kw-*, type-*, phase-*, screen-*, fn-*, annot-*, op-*)
  instead of a single scrolling page; namespace overview pages (ns-screen …
  ns-color) and a searchable index (api.html) with client-side fuzzy search.
- Sticky-header scroll offset (scroll-margin) so a jumped-to entry/param/color is
  never hidden, plus a flash highlight on the scrolled-to target.

Deep linking in every snippet & example
- Namespace members split: `Screen`→namespace page, `fill_rectangle`→method page;
  `Color`→palette page, `Charcoal`→its swatch — separately.
- Named arguments (`width:`) link to that parameter's anchor on the method page.
- Hover any token for a summary card built from the real API data (symbols.json).

Content & coverage
- Full authoritative surface documented from the compiler: every keyword, type,
  the 6 phases (Start/Input/FixedUpdate/Update/LateUpdate/Render, each its own
  page), all 22 annotations, namespace methods with parameter docs, builtins,
  the world_* reflection ABI, networking, operators — 155 symbols.
- Longer, clearer explanations; "model"/"model instance" terminology, not "entity";
  descriptive identifiers in every example (Position{column,row}, Velocity{delta_x,
  delta_y}, Health{current,maximum}, Player/Enemy) — no Pos/Seg/x/dx.
- Accuracy fixes from compiler ground-truth: world_count() takes no arg,
  world_query_next(property, cursor) arg order, event fields bind by name; dropped
  `when` and `module` (not in the self-hosted parser).

Tooling
- inventory.json + check.py: coverage guard (every symbol has a page), duplicate-
  token guard, and broken-link guard — fail CI so docs can't drift.
- validate.py: compiles every ```ludic example against bin/ludicc (158 compile).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/language/annotations/annot-handles.md

@@ -0,0 +1,33 @@
+---
+id: annot-handles
+name: @Handles
+category: annotations
+kind: annotation
+tokens: @Handles
+sig: @Handles(Event) handler Name { … }
+tip: Declarative hint naming the event or subsystem a handler is responsible for.
+order: 50
+---
+
+<code>@Handles</code> is a declarative annotation that names the event or subsystem a handler (or a whole program) is responsible for. The parser accepts and records it as metadata for analysis and tooling — it does not by itself wire up dispatch, so it documents intent rather than driving execution. When you want a handler to actually run in response to an event, use <code>@On(Event)</code>, which registers the listener; <code>@Handles</code> is the companion label that makes ownership of an event legible across a modular codebase. Keep the named symbol a real event or system so the annotation stays meaningful.
+
+```ludic
+program CombatModule {
+  property Health { current: int = 100 }
+  model Enemy { Health }
+
+  event DamageDealt { amount: int = 0 }
+
+  @Handles(DamageDealt)                              # documents this handler's responsibility
+  @On(DamageDealt) handler ApplyDamage {             # @On does the actual dispatch wiring
+    for (Health) in query [Health, {Enemy}] {
+      Health.current = Health.current - amount
+    }
+  }
+
+  entry {
+    spawn Enemy { Health { current: 100 } }
+    emit DamageDealt(amount: 25)
+  }
+}
+```