feat(config): integrate iris and streamline keybindings

dot_config/fish/functions/_iris_busy.fish

@@ -0,0 +1,15 @@
+function _iris_busy --description 'tell iris a key binding is running a program (start|stop)'
+    # iris (~/.config/iris) learns a command is running from fish_preexec /
+    # fish_postexec, which never fire for programs a key binding starts. Without
+    # this, iris keeps treating the screen as an idle prompt while tv, yazi or
+    # lazygit run: it swallows up/down/tab and can draw its menu over them.
+    # Same messages as iris's own hooks; a no-op outside iris.
+    set -q IRIS_FD; or return 0
+    switch "$argv[1]"
+        case start
+            printf 'IRIS_CMD_START\x00' >&$IRIS_FD 2>/dev/null
+        case stop
+            printf 'IRIS_CMD_STOP:0\x00' >&$IRIS_FD 2>/dev/null
+    end
+    return 0
+end