Building a list gets fast, and Ask hears whole phrases

Both threads again: the engine speeds up one of the most common things code does, and Ask your reading listens for phrases, not just words. First, speed. Building up an array item by item - `list.push(...)` in a loop, the everyday 'collect these results as I go' shape - ran entirely at plain-interpreter speed, because the part of the engine that speeds up hot loops did not know how to compile a push. Now it does: the appends are batched and applied at the end of each pass, and reading back what you just pushed still sees it. That loop now runs about two and a half times faster. It stays exact - a push mixed with a direct index write to the same array in one pass steps aside for the careful path, and the fast path is proven equal to the plain interpreter across thousands of fuzzed programs, gate still 6375 of 6375. Second, memory. Ask your reading now rewards an exact phrase. Before, asking about 'battery storage' scored a page that happened to contain both words somewhere as highly as one that used them together as a phrase. Now the ordered phrase counts for more, so the passage that actually says what you asked rises to the top - weighted by how distinctive the words are, so a phrase of rare words matters and a phrase of common ones barely moves.