Documentation tooltips not shown for operators beginning with a dot

[alcestes]

Describe the bug

Ionide does not show documentation tooltips for operators that begins with a dot (.).

This impacts e.g. operators like .>> or .>>. that are commonly defined for parser combinators mimicking the FParsec API. Not being able to see their documentation can be detrimental to their use.

Steps to reproduce

1. Create test.fx with the following content:

   /// This documentation will be shown in a tooltip
   let (>>.) x y = x + y
   
   /// This documentation will NOT be shown in a tooltip
   let (.>>) x y = x + y
   
   /// This documentation will NOT be shown in a tooltip, either
   let (.>>.) x y = x + y
   
   let z = 1 >>. 2 .>>. 3 .>> 4
   printf $"{z}"

2. Place the mouse pointer on line 10 over the operator >>.: the expected documentation tooltip will appear.

3. Place the mouse pointer on line 10 over the operator .>>. or .>>: the documentation tooltip will not appear.

Expected behaviour

The documentation tooltip should appear when the mouse pointer is placed over any operator, even if its name begins with a dot ..

Machine infos

• OS: Linux (Ubuntu 24.04 and 25.10)
• .NET SDK version: 10.0.100
• Ionide version: 7.30.0