feat(waybar): add Thunderbird inbox-unread module

Polls the protonmail-bridge IMAP socket every 60s with STATUS INBOX
(UNSEEN), displays the count next to the tray, and clicking the badge
runs tb-toggle.sh to bring TB out of the scratchpad (or launch it).

Setup: store bridge credentials in pass at email/protonmail-bridge/{user,
pass}. The bridge surfaces them via 'protonmail-bridge --cli' -> 'info'.
With no entries (or with the bridge unreachable) the module shows
'MAIL ?' in red and is otherwise inert.

1 files changed, 14 insertions, 1 deletions

diff --git a/dot_config/waybar/style.css b/dot_config/waybar/style.css
index f631736..037c0e3 100644
--- a/dot_config/waybar/style.css
+++ b/dot_config/waybar/style.css
@@ -47,7 +47,8 @@ window#waybar {
 #privacy,
 #custom-memory,
 #custom-wifi,
-#custom-notifications {
+#custom-notifications,
+#custom-thunderbird {
   padding: 0 6px;
 }
 
@@ -115,6 +116,18 @@ window#waybar {
   color: #fe8019; /* orange — unread */
 }
 
+#custom-thunderbird {
+  color: #928374; /* gray when inbox is empty */
+}
+
+#custom-thunderbird.unread {
+  color: #fe8019; /* orange — has unread mail */
+}
+
+#custom-thunderbird.error {
+  color: #fb4934; /* red — bridge down or creds missing */
+}
+
 #battery.warning {
   color: #fabd2f;
 }