feat(terminology): workplan-first dashboard and retirement backlog (STATE-WP-0069)

Add the ranked legacy-interface backlog (T01), rename dashboard navigation and
user-facing copy to workplan while preserving wire-compat API keys (T02), and
activate the retirement workplan with T01/T02 marked done.

dashboard/test/terminology-nav.test.mjs

@@ -0,0 +1,21 @@
+import assert from "node:assert/strict";
+import {readFileSync} from "node:fs";
+import test from "node:test";
+import {fileURLToPath} from "node:url";
+import {dirname, join} from "node:path";
+
+const root = join(dirname(fileURLToPath(import.meta.url)), "..");
+const config = readFileSync(join(root, "observablehq.config.js"), "utf8");
+const indexMd = readFileSync(join(root, "src/index.md"), "utf8");
+
+test("dashboard navigation uses workplan labels", () => {
+  assert.match(config, /name: "Workplans"/);
+  assert.doesNotMatch(config, /name: "Workstreams"/);
+});
+
+test("overview page uses workplan-first user-facing copy", () => {
+  assert.match(indexMd, /## Workplans by Repository/);
+  assert.match(indexMd, /Active Workplans/);
+  assert.doesNotMatch(indexMd, /No active workstreams\./);
+  assert.doesNotMatch(indexMd, /Active Workstreams/);
+});