chore: keep the internal view id out of the release banner (closes #375)

The debug/testnet banner appended the active view's internal id, so the
user saw text like "[TESTNET] (approve-tx)" — developer vocabulary, and on
the approval screen it sat directly above the carefully worded line stating
what is being authorized. The view id is now gated on the compile-time
DEBUG constant instead of isDebug(), so it survives only in a debug build.
A testnet or the runtime debug toggle still raises the banner, but without
the view id, which is what a release build shows.

Model: opus-4-8

src/popup/views/helpers.js

@@ -12,6 +12,7 @@
 // escapeHtml lives in src/shared/html.js, where the escape and the
 // reasoning behind it are; it is re-exported below so views keep importing
 // it from here.
+const { DEBUG } = require("../../shared/constants");
 const { escapeHtml } = require("../../shared/html");
 const { isDebug } = require("../../shared/log");
 const { formatUsd, getPrice } = require("../../shared/prices");
@@ -119,7 +120,11 @@ function updateDebugBanner(viewName) {
                 "background:#c00;color:#fff;text-align:center;font-size:10px;padding:1px 0;font-family:monospace;position:sticky;top:0;z-index:9999;";
             document.body.prepend(banner);
         }
-        const suffix = viewName ? " (" + viewName + ")" : "";
+        // The view id is internal vocabulary; it helps while developing but
+        // means nothing to a user. Only a debug build appends it, gated on the
+        // compile-time DEBUG constant so a release build never shows it — not
+        // isDebug(), which is also true for a testnet or the runtime toggle.
+        const suffix = DEBUG && viewName ? " (" + viewName + ")" : "";
         if (debug && net.isTestnet) {
             banner.textContent = "DEBUG / INSECURE [TESTNET]" + suffix;
         } else if (net.isTestnet) {