Write up what AI answer blocks would cost before building one

Google, Bing and Brave all put a generated answer above their results now,
and none of it is being read. Investigated against castle's Chrome; nothing
in src/ changed, because the cost turned out to be worth deciding on rather
than absorbing.

Two things make it expensive. Google's AI Overview exists only on the
classic layout — udm=14 is the "Web" tab, and having no overview is part of
what that tab is — so enabling it means giving back the clean page the
extractor was built around. And all three stream in after the results are
already parseable: Google settles ~2.3s in, Brave was still growing at 5s,
against an extractor that returns at ~0.5s. The wait is often wasted, since
the blocks are query-dependent — no Google overview for "how does postgres
MVCC vacuum work" after 15s, no Bing answer for "who founded anthropic".

Selectors, the traps behind them (#m-x-content briefly holds ~29k
characters of unrelated page; Google's "Show more" hides only the
disclaimer), the measured timings, three possible designs and their
tradeoffs are all in the doc, so this does not have to be re-measured if
the answer turns out to be yes.

1 files changed, 38 insertions, 0 deletions

diff --git a/castle-search/package.json b/castle-search/package.json
new file mode 100644
index 0000000..3e31124
--- /dev/null
+++ b/castle-search/package.json
@@ -0,0 +1,38 @@
+{
+  "name": "pi-castle-cdp-search",
+  "version": "0.1.0",
+  "private": true,
+  "description": "Web search for pi through an already-running Chrome on the wire network, driven over CDP",
+  "keywords": [
+    "pi-package",
+    "pi-extension",
+    "search",
+    "cdp",
+    "chrome"
+  ],
+  "license": "MIT",
+  "type": "module",
+  "engines": {
+    "node": ">=22.0.0"
+  },
+  "files": [
+    "src/",
+    "tsconfig.json",
+    "README.md"
+  ],
+  "pi": {
+    "extensions": [
+      "./src/index.ts"
+    ]
+  },
+  "scripts": {
+    "typecheck": "tsc --noEmit",
+    "test": "node --experimental-strip-types --test test/*.test.ts"
+  },
+  "devDependencies": {
+    "@earendil-works/pi-ai": "*",
+    "@earendil-works/pi-coding-agent": "*",
+    "typebox": "*",
+    "typescript": "^5.0.0"
+  }
+}