Wrap native text within occurrence constraints and preserve paint bounds

src/api.rs

@@ -1083,7 +1083,9 @@ Window is a host-provided managed resource: ui.window(), page.window(), page.ope
 
 ContainerBlock.insert(position,block) accepts a zero-based position through the current count, returns a new stable slot and preserves existing slots/Mounts. Invalid indices and child cycles fail before changing the child list. Page.moveTab(position) uses a final zero-based index in its owning window. Native drops invoke the actual Page moveToWindow/moveTab/activate methods; a declined or redirected window move skips destination reordering. A drop allows 300000 instructions per method. Source overrides participate; earlier writes do not roll back after failure. Window.moveTo(x,y) queues the physical desktop outer origin, with signed integers within +/-1000000. Detached placement preserves the saved grab offset; the window manager may adjust it and unsupported global placement reports a diagnostic. Dragging uses a 12-logical-pixel threshold, visible insertion marker and Escape cancellation. Overflow auto-scroll, external-app occlusion and mixed-DPI verification remain pending. See examples/tab-placement.endor.
 
-Source measure and arrange overrides execute bottom-up and top-down in one read-only VM layout call. Structural Mount links exist before first measurement; bounds queries reject premature geometry. Native base layout uses current occurrence child measurements, and Arrangement must assign every stable child slot exactly once. Layout dependencies changed by lifecycle hooks trigger another pass before publication. Page constraints now use the current logical window viewport. Column/Button propagate cross-axis width and Row propagates cross-axis height; desired sizes are clamped. ui.viewport() provides a managed snapshot whose private input participates in rendering dependencies. Native resize updates are coalesced on the same worker without adding source inputs. Source measurement caches use Mount/method/children/constraints and actual subcall object reads, including returned-result decoding; Mount-reading methods conservatively bypass caching. ui.stats() exposes sourceMeasureHits/sourceMeasureMisses outside read-only rendering. General constraint negotiation and text wrapping remain pending; ScrollBlock scrolling is described below.
+Source measure and arrange overrides execute bottom-up and top-down in one read-only VM layout call. Structural Mount links exist before first measurement; bounds queries reject premature geometry. Native base layout uses current occurrence child measurements, and Arrangement must assign every stable child slot exactly once. Layout dependencies changed by lifecycle hooks trigger another pass before publication. Page constraints now use the current logical window viewport. Column/Button propagate cross-axis width and Row propagates cross-axis height; desired sizes are clamped. ui.viewport() provides a managed snapshot whose private input participates in rendering dependencies. Native resize updates are coalesced on the same worker without adding source inputs. Source measurement caches use Mount/method/children/constraints and actual subcall object reads, including returned-result decoding; Mount-reading methods conservatively bypass caching. ui.stats() exposes sourceMeasureHits/sourceMeasureMisses outside read-only rendering. Native TextBlock wrapping now uses the occurrence width in measurement/cache/painting; general constraint negotiation remains pending; ScrollBlock scrolling is described below.
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+TextBlock now wraps words/glyphs at its available width and measures the resulting height. Native and source-base measurement paths use current constraints; native shape/font caches include wrap width. Painting carries allocated width/height, clips glyphs and keeps ancestor scroll clipping. Source text PaintCommand may supply both wrapWidth/wrapHeight (finite nonnegative logical dimensions up to 1000000); neither preserves legacy unwrapped paint, and a partial pair is rejected. Native TextBlock.paint supplies the pair. These are derived draw bounds, not another business object. Management UI text remains unwrapped. General flex/constraint convergence, vertical-only scrolling policy and broad fractional-DPI validation remain pending. See examples/wrapped-text.endor.
 
 Source paint overrides execute in the actual frame pipeline under a read-only heap policy. Source hitTest overrides similarly refine native pointer targets in VM paint order; Point.inside(bounds) and Point.inCircle(cx, cy, radius) provide primitive shape queries. Managed DisplayList/ObjectList/PaintCommand and Constraints/Bounds/Point results are ordinary runtime objects.