[BUG] Fix adding empty named IOKey in Connect

[kberat-synnada]

Bug Report

Describe the Bug

Raises exception while adding empty named IOKey in Connect. The error is triggered only if summary is called.

To Reproduce

model = Model()
model += (add := Add())
model += Add()(left = Connect(add.left, key=IOKey("")))
model.summary()

Expected Behavior

The code above should run without a problem.

System Info

• OS: macOS Sonoma 14.5
• Mithril Version: 0.1.1
• Torch Version: 2.4.1
• MLX Version: 0.18.0
• NumPy Version: 2.1.2
• JAX Version: 0.4.34
• Python Version: 3.12.7

[ozankabak]

Is this still an issue?