feat: modernize and harden bot deployment

src/scoring_test.ts

@@ -0,0 +1,19 @@
+import { assertAlmostEquals, assertThrows } from "@std/assert";
+import { reactionWeight, scoreForUser, totalScore } from "./scoring.ts";
+
+Deno.test("one reaction by one user scores one point", () => {
+  assertAlmostEquals(scoreForUser(1), 1);
+});
+
+Deno.test("repeat reactions by one user have diminishing weight", () => {
+  assertAlmostEquals(reactionWeight(2), 1 / 3);
+  assertAlmostEquals(scoreForUser(3), 1 + 1 / 3 + 1 / 5);
+});
+
+Deno.test("total score sums each user's score", () => {
+  assertAlmostEquals(totalScore([1, 1, 2]), 3 + 1 / 3);
+});
+
+Deno.test("invalid reaction counts are rejected", () => {
+  assertThrows(() => scoreForUser(0), RangeError);
+});