feat: add generate strong password button to Add Members form

Add a "Generate strong password" button with Sparkles icon to the
Add Members form in Settings > People. Generated passwords are shown
in plain text with a copy button and an amber warning to copy before
creating the user. Also upgraded the button style on the change
password page to match. Translated copy/warning strings for all 21
locales.

Closes #139

packages/shared/src/i18n/en.ts

@@ -1457,6 +1457,10 @@ export const en = {
       resetPasswordAction: "Reset Password",
       deleteUserAction: "Delete User",
       saveButton: "Save",
+      copyPasswordButton: "Copy password",
+      passwordCopied: "Copied!",
+      copyPasswordWarning:
+        "Copy this password now. You won't be able to see it after creating the user.",
     },
     teams: {
       heading: "Teams",