fix: Blockscout and Etherscan lookups are off until the user turns them on (closes #668)

Out of the box the wallet sent the user's addresses to Blockscout and each recipient's address to Etherscan. Two settings, "Use Blockscout" and "Check recipients on Etherscan", now gate every request that sends the user's data to those services. Both start off and are offered unticked on Welcome and in Settings. Each request reads its setting from storage before it asks. An answer that lands after the setting went off is dropped. While a setting is off, the screens that rely on it say so. ENS lookups ask only the RPC endpoint, so a name resolved off-chain does not resolve.

RULES.md's External Communication item is now out of date. Its new wording will be proposed on #211 once this lands.

Model: opus-5-5 (implementation, summary); fable-5-1 (prose)

tests/e2e/network.js

@@ -653,6 +653,12 @@ function traceEnabled(raw) {
  *   confirmed receipt instead of null, so a wait screen resolves.
  * @param {boolean} [opts.failReceiptLookup]  answer eth_getTransactionReceipt
  *   with an error, so every receipt lookup fails; read at request time.
+ * @param {string} [opts.etherscanLabel]  the label Etherscan's page gives the
+ *   address asked about, such as "Fake_Phishing1"; none when unset. Read at
+ *   request time.
+ * @param {object[]} [opts.requests]  a list for the requests this handler
+ *   sees. Each is appended in order as { method, url, fromWorker }, whether it
+ *   came from a popup page or the background worker.
  * @returns {Promise<{waitForServiceWorkerTraffic: (ms: number) =>
  *   Promise<string|null>}>}
  */
@@ -691,6 +697,13 @@ async function installNetworkStubs(ctx, opts) {
             const origin = fromWorker ? "[sw] " : "[page] ";
             console.log("# routed " + origin + req.method() + " " + req.url());
         }
+        if (Array.isArray(opts.requests)) {
+            opts.requests.push({
+                method: req.method(),
+                url: req.url(),
+                fromWorker,
+            });
+        }
 
         // JSON-RPC endpoint (any host): a POST with a JSON-RPC body.
         if (req.method() === "POST") {
@@ -762,12 +775,20 @@ async function installNetworkStubs(ctx, opts) {
             return route.fulfill({ status: 204, body: "" });
         }
 
-        // Best-effort Etherscan address labels: served as an empty page.
+        // Best-effort Etherscan address labels: served as an empty page, or
+        // as a page labelling the address with opts.etherscanLabel.
         if (url.hostname.endsWith("etherscan.io")) {
+            const title = opts.etherscanLabel
+                ? "<title>" +
+                  opts.etherscanLabel +
+                  " | Address: " +
+                  p.split("/").pop() +
+                  " | Etherscan</title>"
+                : "";
             return route.fulfill({
                 status: 200,
                 contentType: "text/html",
-                body: "<html><body></body></html>",
+                body: "<html><head>" + title + "</head><body></body></html>",
             });
         }