Make cross-signing dialog clearer and more context-aware

- Don't show loading spinners while waiting for user action
- When checking if there are other devices we can verify against, only
  look for devices that are actually cross-signed.
- Adjust displayed options depending on whether other devices and/or
  recovery keys exist, and add an option to reset cross-signing keys
  if necessary.
- Various minor clarifying adjustments to UI styling/text

Signed-off-by: Faye Duxovni <fayed@element.io>

src/i18n/strings/en_EN.json

@@ -938,8 +938,8 @@
     "Verify this session by confirming the following number appears on its screen.": "Verify this session by confirming the following number appears on its screen.",
     "Verify this user by confirming the following number appears on their screen.": "Verify this user by confirming the following number appears on their screen.",
     "Unable to find a supported verification method.": "Unable to find a supported verification method.",
-    "Waiting for your other session, %(deviceName)s (%(deviceId)s), to verify…": "Waiting for your other session, %(deviceName)s (%(deviceId)s), to verify…",
-    "Waiting for your other session to verify…": "Waiting for your other session to verify…",
+    "Waiting for you to verify on your other session, %(deviceName)s (%(deviceId)s)…": "Waiting for you to verify on your other session, %(deviceName)s (%(deviceId)s)…",
+    "Waiting for you to verify on your other session…": "Waiting for you to verify on your other session…",
     "Waiting for %(displayName)s to verify…": "Waiting for %(displayName)s to verify…",
     "Cancelling…": "Cancelling…",
     "They match": "They match",
@@ -1791,7 +1791,7 @@
     "In encrypted rooms, like this one, URL previews are disabled by default to ensure that your homeserver (where the previews are generated) cannot gather information about links you see in this room.": "In encrypted rooms, like this one, URL previews are disabled by default to ensure that your homeserver (where the previews are generated) cannot gather information about links you see in this room.",
     "When someone puts a URL in their message, a URL preview can be shown to give more information about that link such as the title, description, and an image from the website.": "When someone puts a URL in their message, a URL preview can be shown to give more information about that link such as the title, description, and an image from the website.",
     "Back": "Back",
-    "Accept on your other login…": "Accept on your other login…",
+    "To proceed, please accept the verification request on your other login.": "To proceed, please accept the verification request on your other login.",
     "Waiting for %(displayName)s to accept…": "Waiting for %(displayName)s to accept…",
     "Accepting…": "Accepting…",
     "Start Verification": "Start Verification",
@@ -2949,8 +2949,11 @@
     "Could not load user profile": "Could not load user profile",
     "Decrypted event source": "Decrypted event source",
     "Original event source": "Original event source",
+    "Unable to verify this login": "Unable to verify this login",
     "Verify this login": "Verify this login",
     "Session verified": "Session verified",
+    "Really reset verification keys?": "Really reset verification keys?",
+    "Skip verification for now": "Skip verification for now",
     "Failed to send email": "Failed to send email",
     "The email address linked to your account must be entered.": "The email address linked to your account must be entered.",
     "A new password must be entered.": "A new password must be entered.",
@@ -3004,13 +3007,18 @@
     "Create account": "Create account",
     "Host account on": "Host account on",
     "Decide where your account is hosted": "Decide where your account is hosted",
-    "Use Security Key or Phrase": "Use Security Key or Phrase",
-    "Use Security Key": "Use Security Key",
-    "Use another login": "Use another login",
+    "It looks like you don't have a Security Key or any other devices you can verify against.  This device will not be able to access old encrypted messages. In order to verify your identity on this device, you'll need to reset your verification keys.": "It looks like you don't have a Security Key or any other devices you can verify against.  This device will not be able to access old encrypted messages. In order to verify your identity on this device, you'll need to reset your verification keys.",
+    "Proceed with reset": "Proceed with reset",
+    "Verify with Security Key or Phrase": "Verify with Security Key or Phrase",
+    "Verify with Security Key": "Verify with Security Key",
+    "Verify with another login": "Verify with another login",
     "Verify your identity to access encrypted messages and prove your identity to others.": "Verify your identity to access encrypted messages and prove your identity to others.",
     "Your new session is now verified. It has access to your encrypted messages, and other users will see it as trusted.": "Your new session is now verified. It has access to your encrypted messages, and other users will see it as trusted.",
     "Your new session is now verified. Other users will see it as trusted.": "Your new session is now verified. Other users will see it as trusted.",
     "Without verifying, you won’t have access to all your messages and may appear as untrusted to others.": "Without verifying, you won’t have access to all your messages and may appear as untrusted to others.",
+    "I'll verify later": "I'll verify later",
+    "Resetting your verification keys cannot be undone. After resetting, you won't have access to old encrypted messages, and any friends who have previously verified you will see security warnings until you re-verify with them.": "Resetting your verification keys cannot be undone. After resetting, you won't have access to old encrypted messages, and any friends who have previously verified you will see security warnings until you re-verify with them.",
+    "Please only proceed if you're sure you've lost all of your other devices and your security key.": "Please only proceed if you're sure you've lost all of your other devices and your security key.",
     "Failed to re-authenticate due to a homeserver problem": "Failed to re-authenticate due to a homeserver problem",
     "Incorrect password": "Incorrect password",
     "Failed to re-authenticate": "Failed to re-authenticate",