harden: end a site's unremembered connection when its address or wallet is removed (closes #245)

A site connected without "Remember" lives only in the background's
in-memory connectedSites map. Removing an address or deleting a wallet
dropped the remembered permissions but never told the background; the
entry went only as a side effect of the accountsChanged broadcast, which
empties the whole map when the active address changes.

dropSitePermissions(), shared by both removal paths, now sends
AUTISTMASK_ADDRESSES_REMOVED with the removed addresses, and the
background deletes their entries. Only the extension's own pages may
send it.

Model: opus-5-5

TODO.md

@@ -45,6 +45,17 @@ but the review is broader than any of them.
 
 # Completed Steps
 
+- 2026-10-04: Removing an address or deleting a wallet ends every site
+  connection approved without "Remember" for the addresses removed
+  ([#245](https://git.eeqj.de/sneak/AutistMask/issues/245)). Such a connection
+  lives only in the background's in-memory `connectedSites` map. Both removal
+  paths dropped the remembered `allowedSites`/`deniedSites` entries, but nothing
+  told the background, so its entry was cleared only as a side effect: every
+  change of active address empties the whole map, and removing the active
+  address changes it. `dropSitePermissions()` in `src/shared/walletDelete.js`,
+  shared by both paths, now also sends `AUTISTMASK_ADDRESSES_REMOVED` with the
+  removed addresses, and the background deletes their `connectedSites` entries;
+  only the extension's own pages may send it.
 - 2026-10-03: The typed-data signing screen warns for a token permission, and
   names the primary type ethers signs
   ([#400](https://git.eeqj.de/sneak/AutistMask/issues/400)). A Permit or Permit2