Wire mode cursor breaks after connection is made

[cdriesler]

Reproduction:

• Start a wire connection from any port
• Complete the wire connection anywhere
• Move the cursor, while still over a port
• Observe that cursor does not re-appear until you re-enter a port's capture area
• Observe 🐍 errors in console explaining that it could not find a mode

Explanation:

Wire mode cursor drawing requires a "mode" to be set so we know which kind of connection icon to show (i.e. set, merge, remove). This information is cleared when a live wire is committed as a real wire, but the cursor is likely still over a port.

Likely fixable by not clearing the cursor information (maybe just mode?) on wire commit.