Fix: preserve type applications in record patterns

[mgajda]

Fixes #1679

Problem

HLint was suggesting record pattern syntax that removes type applications, producing invalid code.

Example

-- Original (with type applications):
Ast.AstScatterS @_ @shn1 @shp1 _ _ _ _ _

-- HLint suggested (WRONG):
Ast.AstScatterS {}

Result: Type applications are lost, code doesn't parse!

Root Cause

The record pattern suggestion in patHint didn't check if the constructor had type arguments. It would suggest the record syntax {} even when type applications were present, which would strip them away.

Solution

Check if the PrefixCon pattern has any type arguments before suggesting record pattern conversion. If type arguments exist, skip the suggestion.

Changes

• Modified patHint in src/Hint/Pattern.hs to check for empty type argument list
• Added test cases for patterns with and without type applications

Testing

Test cases verify:

• foo (Bar _ _ _ _) = x → suggests Bar{} (normal case works)
• foo (Bar @A @B _ _ _) = x → no suggestion (multiple type apps preserved)

All existing tests pass.