Large values in registers display incorrectly

[TemariVirus]

Describe the bug
Large values in registers are not displayed correctly. The loss of precision is reminiscent of that of JS floating point.

To Reproduce
Steps to reproduce the behavior:

1. Create a binary that stores a large value in a register, like with or $0xffffffffffffffff, %rax
2. Load the binary in gdbgui and run starti
3. Step past the instruction

Expected behavior
The value in rax should be displayed as 0xffffffffffffffff and 18446744073709551615.

Actual behaviour

Please complete the following information:

• OS: Linux 6.18.25, NixOS 25.11
• gdbgui version (gdbgui -v): 0.15.3.0
• gdb version (gdb -v): 16.3
• browser [e.g. chrome, safari]: LibreWolf 150.0-1
• python packages (pip freeze): (Nix unpins the versions in requirements.txt before building)

bidict==0.23.1
blinker==1.9.0
Brotli==1.2.0
click==8.2.1
dnspython==2.8.0
eventlet==0.40.0
Flask==3.1.2
Flask-Compress==1.17
Flask-SocketIO==5.5.1
greenlet==3.2.3
h11==0.16.0
itsdangerous==2.2.0
Jinja2==3.1.6
MarkupSafe==3.0.3
pygdbmi==0.11.0.0
Pygments==2.19.2
python-engineio==4.12.3
python-socketio==5.14.3
simple-websocket==1.1.0
six==1.17.0
Werkzeug==3.1.4
wsproto==1.2.0
zstandard==0.23.0

Additional context

18446744073709551615 + '' evaluates to '18446744073709552000' in JS.