incremental: add test for changing container kind

This used to trigger bugs, but works correctly as of Zig 0.16.0.

Resolves: https://github.com/ziglang/zig/issues/24217

test/incremental/change_container_kind

@@ -0,0 +1,61 @@
+#update=initial version, T is struct
+#file=main.zig
+const T = @import("foo.zig").T;
+pub fn main() void {
+    @compileLog(T);
+    @compileLog(@tagName(@typeInfo(T)));
+}
+#file=foo.zig
+pub const T = struct { x: u8 };
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [6:0]u8, "struct")
+
+#update=T is union
+#file=foo.zig
+pub const T = union {};
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [5:0]u8, "union")
+
+#update=T is enum
+#file=foo.zig
+pub const T = enum {};
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [4:0]u8, "enum")
+
+#update=T is opaque
+#file=foo.zig
+pub const T = opaque {};
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [6:0]u8, "opaque")
+
+#update=T is packed struct
+#file=foo.zig
+pub const T = packed struct {};
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [6:0]u8, "struct")
+
+#update=T is packed union
+#file=foo.zig
+pub const T = packed union { x: void }; // packed unions need at least 1 field
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [5:0]u8, "union")
+
+#update=T is extern struct
+#file=foo.zig
+pub const T = extern struct {};
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [6:0]u8, "struct")
+
+#update=T is extern union
+#file=foo.zig
+pub const T = extern union { x: void }; // extern unions need at least 1 field
+#expect_error=main.zig:3:5: error: found compile log statement
+#expect_compile_log=@as(type, foo.T)
+#expect_compile_log=@as(*const [5:0]u8, "union")