GTK: `title` config should be respected and set immediately on new windows, tabs

[mitchellh]

Discussed in #5836

^{Originally posted by vaygr February 17, 2025}
Steps to reproduce:

yabai -m rule --add app="Ghostty" title="^scratchterm$" scratchpad="scratchterm" grid=5:5:1:0:3:3
open -na Ghostty.app --args --title="scratchterm"

Even though the title is reported correctly once ghostty is launched:

{
        "id":5281,
        "pid":13867,
        "app":"Ghostty",
        "title":"scratchterm",
        "scratchpad":"",
        "frame":{
                "x":12.0000,
                "y":50.0000,
                "w":1488.0000,
                "h":920.0000
        },
        "role":"AXWindow",
        "subrole":"AXStandardWindow",
        "root-window":true,
        "display":1,
        "space":1,
        "level":0,
        "sub-level":-20,
        "layer":"normal",
        "sub-layer":"below",
        "opacity":1.0000,
        "split-type":"vertical",
        "split-child":"second_child",
        "stack-index":0,
        "can-move":true,
        "can-resize":true,
        "has-focus":true,
        "has-shadow":true,
        "has-parent-zoom":false,
        "has-fullscreen-zoom":true,
        "has-ax-reference":true,
        "is-native-fullscreen":false,
        "is-visible":true,
        "is-minimized":false,
        "is-hidden":false,
        "is-floating":false,
        "is-sticky":false,
        "is-grabbed":false
}

But the rule never gets triggered, that is unless I remove title argument for yabai -m rule or set it to ^.*$.

I tested it with kitty to see if it could be yabai's issue, but no, it worked as expected:

yabai -m rule --add app="kitty" title="^scratchterm$" scratchpad="scratchterm" grid=5:5:1:0:3:3
kitty --title "scratchterm"

My assumption is ghostty could be setting the title a bit too late?

Notes

Right now, the core Surface sends a set_title apprt action AFTER the surface is initialized, which -- at least for macOS -- happens to be after the Window (tabs are also windows in macOS) is created.

If the user sets an explicit title config, we should set that as part of the window creation process rather than wait for this message.