parameterize ctrl thread registers cache with entity store, rather than relying on implicit demon-api-provided cache

src/regs/generated/regs.meta.c

@@ -5,7 +5,7 @@
 
 internal U64 regs_block_size_from_architecture(Architecture arch)
 {
-U64 result = 0;
+U64 result = 8;
 switch(arch)
 {
 default:{}break;

src/regs/regs.mdesk

@@ -421,7 +421,7 @@ regs_g_reg_code_x86_usage_kind_table:
 {
   `internal U64 regs_block_size_from_architecture(Architecture arch)`;
   `{`;
-    `U64 result = 0;`;
+    `U64 result = 8;`;
     `switch(arch)`;
     `{`;
       `default:{}break;`;