fix: handle custom local names for widened types (#2401)

fixes #2397

`pass.Pkg.Imports()` did not always* include the local name alias from
the import statement, so instead we need to do our checks via `PkgName`
which does include it.

*it includes it in the example in our tests, but didn't in the case that
our partner project was hitting...
I've added another test case that previously failed like theirs did.

go-runtime/schema/schema_test.go

@@ -195,6 +195,9 @@ func TestExtractModuleSchemaTwo(t *testing.T) {
 	}
 	actual := schema.Normalise(r.Module)
 	expected := `module two {
+			typealias BackoffAlias Any
+        		+typemap go "github.com/jpillora/backoff.Backoff"
+        
 			typealias ExplicitAliasAlias Any
 				+typemap kotlin "com.foo.bar.NonFTLType"
 				+typemap go "github.com/TBD54566975/ftl/go-runtime/schema/testdata.lib.NonFTLType"

go-runtime/schema/testdata/two/go.mod

@@ -4,7 +4,10 @@ go 1.22.2
 
 replace github.com/TBD54566975/ftl => ../../../..
 
-require github.com/TBD54566975/ftl v0.150.3
+require (
+	github.com/TBD54566975/ftl v0.150.3
+	github.com/jpillora/backoff v1.0.0
+)
 
 require (
 	connectrpc.com/connect v1.16.2 // indirect
@@ -26,7 +29,6 @@ require (
 	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
 	github.com/jackc/pgx/v5 v5.6.0 // indirect
 	github.com/jackc/puddle/v2 v2.2.1 // indirect
-	github.com/jpillora/backoff v1.0.0 // indirect
 	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/multiformats/go-base36 v0.2.0 // indirect

go-runtime/schema/testdata/two/two.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/TBD54566975/ftl/go-runtime/ftl"
 	lib "github.com/TBD54566975/ftl/go-runtime/schema/testdata"
+	libbackoff "github.com/jpillora/backoff"
 
 	"ftl/builtin"
 )
@@ -103,6 +104,9 @@ type TransitiveAliasAlias = lib.NonFTLType
 
 type TransitiveAlias lib.NonFTLType
 
+//ftl:typealias
+type BackoffAlias libbackoff.Backoff
+
 func transitiveVerbCall(ctx context.Context, req Payload[string]) error {
 	_, err := ftl.Call(ctx, Two, req)
 	if err != nil {

go-runtime/schema/typealias/analyzer.go

@@ -86,16 +86,14 @@ func qualifiedNameFromSelectorExpr(pass *analysis.Pass, node ast.Node) string {
 	if !ok {
 		return ""
 	}
-	for _, im := range pass.Pkg.Imports() {
-		if im.Name() != ident.Name {
-			continue
-		}
-		fqName := im.Path()
-		if parts := strings.Split(im.Path(), "/"); parts[len(parts)-1] != ident.Name {
-			// if package differs from the directory name, add the package name to the fqName
-			fqName = fqName + "." + ident.Name
-		}
-		return fqName + "." + se.Sel.Name
+	pkgName, ok := pass.TypesInfo.ObjectOf(ident).(*types.PkgName)
+	if !ok {
+		return ""
+	}
+	fqName := pkgName.Imported().Path()
+	if parts := strings.Split(fqName, "/"); parts[len(parts)-1] != pkgName.Imported().Name() {
+		// if package differs from the directory name, add the package name to the fqName
+		fqName = fqName + "." + ident.Name
 	}
-	return ""
+	return fqName + "." + se.Sel.Name
 }