fix(auth): stop the address-bar mirror eating emailed auth tokens, and unlock revoked accounts

Two independent bugs made an email+password registration unrecoverable in prod.

The verification link did nothing. urlWithParams/clearParams rebuilt the URL as
pathname+query and dropped the fragment — but the one-time auth tokens ride the
fragment (#verify=/#reset=, SB3), and the providers that mirror nav params
(useUrlMirror in FeedFilters/Playlists/Plex/Channels) sit ABOVE the lazily-loaded
<App> in main.tsx. Their mount effect replaceState'd the token away before the auth
card's chunk had loaded, so the card read an empty hash: the link opened a bare
sign-in page, no request, no banner. Both helpers now carry the fragment over.

The account was then locked out for good. SEC-10 nulls password_hash when an
unverified account is attested (here: admin approval landing before the user could
verify — which the bug above made impossible). That is indistinguishable from a
Google-only account, and reset eligibility keyed off password_hash alone, so no
reset link was ever issued: no password to sign in with, and no way to get one.
users.password_revoked_at records the revocation, reset eligibility honours it, and
setting a password again (reset-confirm or set-password) clears it. An account that
never had a password stays ineligible on purpose — its owner adds one from Settings.

/auth/verify now also answers password_reset_required so the card can say why the
registered password stopped working, instead of leaving the user at the uniform
"Invalid email or password". Telling the holder of a valid verify token leaks
nothing: they have already proved they own the mailbox.

The 0078 migration backfills the stamp for rows carrying the exact lockout signature
(local, non-demo, no password, unverified), so existing victims recover unaided.

frontend/src/lib/api/auth.ts

@@ -37,7 +37,10 @@ export const authApi = {
       { quiet: true },
     ),
   // Confirm an email-verification token the SPA read from the URL fragment (SB3).
-  verifyEmail: (token: string): Promise<{ ok: boolean }> =>
+  // `password_reset_required` = SEC-10 dropped the password this account registered with (an admin
+  // approved it before it was verified), so signing in would fail with the uniform credentials error.
+  // The card sends the user to the reset flow instead of leaving them to guess.
+  verifyEmail: (token: string): Promise<{ ok: boolean; password_reset_required?: boolean }> =>
     req("/auth/verify", { method: "POST", body: JSON.stringify({ token }) }, { quiet: true }),
   // Re-issue a verification link (the first one expired, or was lost). Uniform response — never
   // reveals whether the email has a pending account.