conlang: Add Tuple-Struct Patterns

- Patterns are no longer parsed with the highest precedence
- Function calls with just a path and a tuple of args can now be transformed into a Pattern

compiler/cl-parser/src/parser.rs

@@ -1080,7 +1080,7 @@ impl Parse<'_> for Return {
 
 impl Parse<'_> for Pattern {
     fn parse(p: &mut Parser<'_>) -> PResult<Self> {
-        let value = prec::exprkind(p, prec::Precedence::Highest.level())?;
+        let value = prec::exprkind(p, prec::Precedence::Pattern.level())?;
         Pattern::try_from(value)
             .map_err(|_| p.error(ExpectedParsing { want: Parsing::Pattern }, Parsing::Pattern))
     }

compiler/cl-parser/src/parser/prec.rs

@@ -255,8 +255,8 @@ pub enum Precedence {
     Index,
     Cast,
     Member, // left-associative
+    Pattern,
     Call,
-    Highest,
 }
 
 impl Precedence {