harden: key remembered site permissions by full origin (closes #402)

allowedSites and deniedSites held the bare hostname, so a grant to
https://dapp.example also authorised http://dapp.example and every port
on that host, and the connection, transaction and signature prompts
named only the hostname. Both lists now store and match the full origin
(scheme://host[:port]), the key the connections approved without
Remember already used. The prompts, the Settings site lists and
AUTISTMASK_REMOVE_SITE use the origin too. Entries saved by hostname
are not migrated (pre-1.0): they match no site.

Model: opus-5-5

tests/contractCreation.test.js

@@ -150,7 +150,7 @@ async function openTxApproval(to, data) {
             if (msg.type !== "AUTISTMASK_GET_APPROVAL") return reply(null);
             reply({
                 type: "tx",
-                hostname: "dapp.example",
+                origin: "https://dapp.example",
                 isPhishingDomain: false,
                 approvedFrom: FROM,
                 approvedTx: {