fix(journal): re-publish only changed declarations

topoSortAffected followed declared dependencies even when they were not in the affected set, so reevaluateDependents re-evaluated and re-published variables that had not changed. This could also overwrite a value just set via /set with the declaration's own expression.

src/cli/completions/variable-system.test.ts

@@ -844,6 +844,25 @@ describe("var-reactivity", () => {
     });
   });
 
+  describe("computeCascade — declarations", () => {
+    test("does not re-publish or re-evaluate declared dependencies that did not change", () => {
+      initReactivity({
+        declarations: [
+          { key: "$con", expression: "12" },
+          { key: "$hp", expression: "$con * 5" },
+        ],
+        tagModifiers: [],
+      });
+
+      // $con was set to 14; only its dependent $hp should be re-evaluated.
+      setBase("$con", "14");
+      const cascade = computeCascade("$con", "12", store({ $con: "14" }));
+
+      expect(cascade.map((r) => r.key)).toEqual(["$hp"]);
+      expect(cascade[0].value).toBe("70");
+    });
+  });
+
   describe("computeCascade — tag activation/deactivation", () => {
     test("activates tag modifiers when a tag value is set", () => {
       initReactivity({