sitesmith: strip diagnostic shim + state-dump now that the fix is verified

Apply path is stable end-to-end with the linkedNode pre-creation patch;
diagnostic shim + window.__sitesmithLastState dump are no longer earning
their footprint. Reverts:
  - vite.config.ts: drops the tiny-invariant alias
  - src/utils/tiny-invariant-shim.ts: deleted
  - PageContext.tsx: removes the post-walk dump/scan block

craft/src/state/PageContext.tsx

@@ -383,25 +383,6 @@ export const PageProvider: React.FC<{ children: ReactNode }> = ({ children }) =>
       return id;
     };
     const rootId = walk(tree, null);
-    // DIAGNOSTIC: dump the produced state + scan for type=undefined nodes
-    // so when the resolver invariant fires we can see which node is bad.
-    try {
-      const w = window as any;
-      w.__sitesmithLastTree = tree;
-      w.__sitesmithLastState = nodes;
-      const bad: Array<{id:string; node:any}> = [];
-      for (const [nid, n] of Object.entries(nodes)) {
-        const t = (n as any).type;
-        const name = t && typeof t === 'object' ? t.resolvedName : t;
-        if (!name) bad.push({ id: nid, node: n });
-      }
-      if (bad.length > 0) {
-        // eslint-disable-next-line no-console
-        console.warn('[SITESMITH] nodes with undefined type:', bad);
-      }
-      // eslint-disable-next-line no-console
-      console.log('[SITESMITH] treeToState produced', Object.keys(nodes).length, 'nodes; rootId=', rootId);
-    } catch (_e) { /* diagnostic only */ }
     // Craft.js deserialize requires the root node keyed as 'ROOT'
     if (rootId !== 'ROOT') {
       nodes['ROOT'] = nodes[rootId];