test: port 944_alias_cgen_b5_run to a compile fixture

944_alias_cgen_b5_run.c -> alias_g73_heapfill (//ww:compile), joining
its migrated alias_* siblings. The carrier's stated fixture blocker
('//ww:compile links') is stale: the COMPILE cell runs the bare
frontend, no link. The live #24 field(SB) deref-read leak enters
DATABYTEID_DIVERGED, upgrading the carrier's silent byte-id waiver
with a graduation tripwire.

internal/wwfixture/types.ww

@@ -1,13 +1,13 @@
 package wwfixture;
 
 def protocolversion: i32 = 1;
-def corpuscount: i32 = 1679;
+def corpuscount: i32 = 1680;
 def errorcount: i32 = 343;
-def compilecount: i32 = 18;
+def compilecount: i32 = 19;
 def runcount: i32 = 209;
 def runexitcount: i32 = 1109;
-def nativecount: i32 = 3358;
-def corpushash: str = "0b3b997170a14de5d526e0d7ce7d5de3c1a33d85db7d029a26e6e01651857b5d";
+def nativecount: i32 = 3360;
+def corpushash: str = "bfc1df1f29f60a79930227b1b93ad01fcbed23a150c3269f1f6befd90e0604d1";
 
 type directive = enum i32 {
 	ERROR = 0,