feat(auth): the recovery key never reaches the hub

Ticking "also e-mail it to me" at registration sent the recovery key R in
the register body, and the hub appended it to the verification e-mail: the
hub saw R in clear on its way out, and the resend door — no captcha — let
anyone who knew a pending username and address have the hub mail a
"recovery key" of their choosing.

The box is gone. The recovery screen offers "E-mail it to myself", a mailto:
link that opens the person's own mail application with the key filled in;
the desktop shell hands mailto: to the system (http, https and mailto only)
and the Android shell to a mail application (ACTION_SENDTO). The CLI drops
--email-recovery-key and prints the key, as before. The hub mails the code
alone, and refuses a register that still carries a recovery_key rather than
dropping it, so an older client offering the option cannot tell someone
their key was sent when it was not.

A mailbox holding R remains, with the reset code that reaches the same
mailbox, enough to recover the account's identities; the link says so, and
it is the person's choice.

Checked in Chrome and Firefox (headless, the real page against a stubbed
hub) and by the CLI's end-to-end registration against a local hub. The
Android change was not built here, and the desktop link was not clicked in
the application.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/static/style.css b/packages/meshbay-hub/src/meshbay_hub/static/style.css
index 07780a2..627f2ca 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/style.css
+++ b/packages/meshbay-hub/src/meshbay_hub/static/style.css
@@ -2661,6 +2661,14 @@ button:disabled { opacity: 0.5; cursor: not-allowed; }
 }
 .btn-secondary:hover { border-color: var(--border); color: var(--text); }
 .btn-secondary:disabled { opacity: 0.4; cursor: not-allowed; }
+/* The recovery screen's "e-mail it to myself": a mailto: link, shaped like the
+   Copy button beside it. */
+a.recovery-mail {
+  display: inline-block;
+  margin: 8px 0 0 8px;
+  border-color: var(--border);
+  text-decoration: none;
+}
 
 /* Text that acts as a button: the "add a description" affordance should not
    compete with the group's name for attention. */