[clang] [clang] Implement P2582R1: CTAD from inherited constructors (PR #98788)

[Aaron Ballman via cfe-commits]

================
@@ -1203,10 +1333,291 @@ void DeclareImplicitDeductionGuidesForTypeAlias(
             ->getDeductionCandidateKind() == DeductionCandidate::Aggregate)
       continue;
 
-    BuildDeductionGuideForTypeAlias(SemaRef, AliasTemplate, F, Loc);
+    BuildDeductionGuideForTypeAlias(SemaRef, AliasTemplate, F, Loc,
+                                    FromInheritedCtor);
   }
 }
 
+// Check if a template is deducible as per [dcl.type.simple]p3
+static bool IsDeducibleTemplate(TemplateDecl *TD) {
----------------
AaronBallman wrote:

```suggestion
static bool IsDeducibleTemplate(const TemplateDecl *TD) {
```
and threaded through the rest of the function?

https://github.com/llvm/llvm-project/pull/98788