mango: show focused window next to tags, fix mmsg lookup, 0.15.x compat

- new focused-window block ({icon} {app_id} - {title}) driven by the
  active_client field of mmsg watch all-monitors (mangowm >= 0.14)
- resolve program icons via freedesktop icon themes/.desktop files
  (new icon module, cairo png feature, cached per app_id)
- new show_focused_window config option (default true)
- run mmsg from PATH instead of hardcoded /usr/bin/mmsg (broken on NixOS)
- handle null active_client fields (no focused client) without failing
  to parse the whole event
- drop stale TODO comment and unused variable in mango provider
- add .justfile run recipe exporting MANGO_INSTANCE_SIGNATURE

1 files changed, 1 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 45a389d..36d4d93 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,6 +12,7 @@ authors = ["MaxVerevkin <maxxverrr@gmail.com>"]
 anyhow = "1"
 memchr = "2"
 pangocairo = "0.20"
+cairo-rs = { version = "0.20", features = ["png"] }
 serde_json = "1"
 serde = { version = "1", features = ["derive"] }
 signal-hook = { version = "0.3", default-features = false }