feat(ui): add DataTable and Toaster, drop the legacy Table, fix overlay dialogs

DataTable replaces the 20-line Table scaffold entirely: columns, sorting,
filtering, pagination, selection, bulk actions, comparison layout, sticky
first column, custom HTML cells, and a remote source driven by a `request`
output rather than a function prop (props travel as HTML attributes, so a
function arrives as its own source text).

Toaster replaces the hand-rolled status div: tone icons, actions, hover
pause/resume and a progress bar.

Overlays audit -- Modal and Drawer declared aria-modal="true" but nothing
ever moved focus into the panel, so the @keydown handler on their root
never ran and closeOnEscape did nothing. Focus, focus restore, a Tab trap
and a body scroll lock now live in the reactive runtime, shared by both.

ContextMenu placed pointer menus by subtracting a guessed 340x420 from the
viewport, which pushed every menu that was not that size away from the
pointer; it now positions at the pointer and lets the anchored clamp pull
it back once it can be measured.

The reactive runtime size budget moves 150k -> 175k to cover anchored
overlays, dialog behaviour, the toaster and the DataTable client half.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

examples/component-showcase/app/pages/components/button.wrn

@@ -254,21 +254,21 @@ page ButtonDetail {
   @click='console.log(payload)'
   @focus='console.log(payload)'
   @blur='console.log(payload)'
-/&gt;</code></pre></section><section class="demo-code"><header><span><span class="icon-[lucide--radio] size-4" aria-hidden="true"></span>Direct output handlers</span><small>.js</small></header><pre><code>import &#123; registerOutputHandler &#125; from "@wrnexus/csr/outputs"
+/&gt;</code></pre></section><section class="demo-code"><header><span><span class="icon-[lucide--radio] size-4" aria-hidden="true"></span>Direct output handlers</span><small>.js</small></header><pre><code>import <span>&#123;</span> registerOutputHandler <span>&#125;</span> from "@wrnexus/csr/outputs"
 
 const component = document.querySelector("[data-ui-component=\"Button\"], [data-component=\"Button\"]")
 
-if (component) registerOutputHandler(component, "click", (payload) =&gt; &#123;
+if (component) registerOutputHandler(component, "click", (payload) =&gt; <span>&#123;</span>
   console.log("click", payload)
-&#125;)
+<span>&#125;</span>)
 
-if (component) registerOutputHandler(component, "focus", (payload) =&gt; &#123;
+if (component) registerOutputHandler(component, "focus", (payload) =&gt; <span>&#123;</span>
   console.log("focus", payload)
-&#125;)
+<span>&#125;</span>)
 
-if (component) registerOutputHandler(component, "blur", (payload) =&gt; &#123;
+if (component) registerOutputHandler(component, "blur", (payload) =&gt; <span>&#123;</span>
   console.log("blur", payload)
-&#125;)</code></pre></section></div></div></section>
+<span>&#125;</span>)</code></pre></section></div></div></section>
         <section id="api" class="detail-section"><div class="detail-section-heading"><span>Component API</span><h2>Props and configuration</h2><p>All content and behavior shown above is supplied through these props and slots.</p></div><div class="docs-table-wrap"><table class="docs-table"><thead><tr><th>Prop</th><th>Type</th><th>Default</th><th>Required</th></tr></thead><tbody><tr><td><code>label</code></td><td>string</td><td><code>"Button"</code></td><td>No</td></tr><tr><td><code>loadingLabel</code></td><td>string</td><td><code>"Loading…"</code></td><td>No</td></tr><tr><td><code>description</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>as</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>href</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>target</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>rel</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>type</code></td><td>string</td><td><code>"button"</code></td><td>No</td></tr><tr><td><code>variant</code></td><td>string</td><td><code>"default"</code></td><td>No</td></tr><tr><td><code>color</code></td><td>string</td><td><code>"primary"</code></td><td>No</td></tr><tr><td><code>size</code></td><td>string</td><td><code>"default"</code></td><td>No</td></tr><tr><td><code>disabled</code></td><td>boolean</td><td><code>false</code></td><td>No</td></tr><tr><td><code>loading</code></td><td>boolean</td><td><code>false</code></td><td>No</td></tr><tr><td><code>pill</code></td><td>boolean</td><td><code>false</code></td><td>No</td></tr><tr><td><code>fullWidth</code></td><td>boolean</td><td><code>false</code></td><td>No</td></tr><tr><td><code>icon</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>iconPosition</code></td><td>string</td><td><code>"start"</code></td><td>No</td></tr><tr><td><code>ariaLabel</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>ariaPressed</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>ariaExpanded</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>ariaControls</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>title</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>autofocus</code></td><td>boolean</td><td><code>false</code></td><td>No</td></tr><tr><td><code>controlClass</code></td><td>string</td><td><code>""</code></td><td>No</td></tr><tr><td><code>class</code></td><td>string</td><td><code>""</code></td><td>No</td></tr></tbody></table></div></section>
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