fix(ui): link the adherence tile straight to the medication wizard and drop dead rail rules

The empty adherence tile linked to the retired /medications/new route,
which only redirects. The sidebar's short-touch rules keyed on a touch
screen at most 520 px tall, where the phone shell hides the rail, so
they could never apply.

src/__tests__/retired-route-links-guard.test.ts

@@ -0,0 +1,43 @@
+/**
+ * Links point at a route that renders, not at a retired one that only
+ * redirects: every hop through a redirect is a round trip on a phone, and
+ * the redirect stubs exist for old bookmarks, not for the app's own links.
+ */
+import { readdirSync, readFileSync, statSync } from "node:fs";
+import { join, relative } from "node:path";
+
+import { describe, expect, it } from "vitest";
+
+const ROOT = join(__dirname, "..", "..");
+
+/** Retired route → where it redirects. */
+const RETIRED: Record<string, string> = {
+  "/medications/new": "/medications?new=1",
+};
+
+function walk(dir: string): string[] {
+  return readdirSync(dir).flatMap((name) => {
+    if (name === "__tests__" || name === "generated") return [];
+    const abs = join(dir, name);
+    if (statSync(abs).isDirectory()) return walk(abs);
+    return /\.tsx?$/.test(name) ? [abs] : [];
+  });
+}
+
+describe("no link targets a retired route", () => {
+  const files = walk(join(ROOT, "src"));
+
+  it("scans the source tree", () => {
+    expect(files.length).toBeGreaterThan(100);
+  });
+
+  it.each(Object.entries(RETIRED))("%s is linked as %s", (route) => {
+    const pattern = new RegExp(
+      `(?:href|push|replace)[=(]\\s*\\{?\\s*["'\`]${route.replace(/\//g, "\\/")}["'\`?#]`,
+    );
+    const offenders = files
+      .filter((file) => pattern.test(readFileSync(file, "utf8")))
+      .map((file) => relative(ROOT, file));
+    expect(offenders).toEqual([]);
+  });
+});