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/sendDisplayFloor.test.js

@@ -232,7 +232,7 @@ async function confirmSend(amount, token = "ETH") {
 async function approveTxWithFeePerGas(maxFeePerGas) {
     approvalDetails = {
         type: "tx",
-        hostname: "dapp.example",
+        origin: "https://dapp.example",
         approvedFrom: HOLDER,
         approvedTx: {
             to: RECIPIENT,