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/operators/op-range.md

@@ -4,8 +4,16 @@ name: Range
 category: operators
 kind: operator
 sig: a .. b
-tip: A half-open range for for loops: a up to but not including b.
+tip: A half-open range for numeric for loops — from a up to but not including b.
 order: 4
 ---
 
-A half-open range for <code>for</code> loops: <code>a</code> up to but not including <code>b</code>.
+`a .. b` is a half-open numeric range used by the counting `for` loop: `for index in a .. b` walks `index` from `a` up to but <b>not including</b> `b`. This "up to but not including" convention makes lengths line up naturally — `0 .. len(route)` visits every element index of a slice, and `0 .. GRID_WIDTH` visits every column with no off-by-one. Both endpoints are `int` expressions, so a bound can be a `const`, a `var`, or any computed value. It is distinct from the string slice `text[start..end]`, which uses the same half-open idea for bytes.
+
+```ludic
+for row in 0 .. GRID_HEIGHT {
+  for column in 0 .. GRID_WIDTH {
+    Screen.put_pixel(x: column, y: row, color: Color.MidnightBlue)
+  }
+}
+```