exp() silently evaluated as a no-op

"exp" was also listed as a scientific-notation alias ("123456 in
exp"). Phrases register first-come-first-served, and that alias was
registered before the exp() function, so the function itself never
got the phrase — exp(1) parsed as a bare (1) and returned 1. Drop
exp from the scientific-notation aliases; sci/exponent/exponential
still work.

src/engine/edge.test.ts

@@ -224,4 +224,12 @@ describe("review fixes", () => {
     expect(calc("$12 * 3")).toBe("$36");
     expect(calc("2 m * 3 m")).toBe("6 m²");
   });
+  it("exp(x) is Euler's number to the power x, not scientific notation", () => {
+    expect(calc("exp(1)")).toBe("2.72");
+    expect(calc("exp(0)")).toBe("1");
+  });
+  it("scientific notation still works via sci/exponent/exponential", () => {
+    expect(calc("123456 in scientific")).toBe("1.23e5");
+    expect(calc("123456 in exponent")).toBe("1.23e5");
+  });
 });

src/engine/vocab-data.ts

@@ -410,7 +410,7 @@ export const EN: VocabLocale = {
     "decimal.variants": "decimal,dec",
     "hex.variants": "hex",
     "octal.variants": "octal",
-    "scientific.variants": "scientific, sci, exp, exponent, exponential"
+    "scientific.variants": "scientific, sci, exponent, exponential"
   },
   "Operations": {
     "assignment.variants": "equal,is",