docs(changelog): link problems using short redirects instead of issue URLs

apps/docs/lib/releases.ts

@@ -12,7 +12,9 @@
  * release-topics.ts's render() writes: `| #issue | LC n · Name | set | diff |
  * closed | [py](…) · [docs](…) |`. Only `### Closed …` sections are read, so
  * a release published before open problems were dropped from the body still
- * shows only what finished.
+ * shows only what finished. The row's own `[docs]` link is not used: it is
+ * frozen at release time (a problem solved before the docs existed has
+ * none), while the page links each problem by its LC number to its page now.
  *
  * Auth: GITHUB_TOKEN when set (deploy.yml passes it), else unauthenticated —
  * one request per 100 releases fits the anonymous limit. A failed request
@@ -26,13 +28,13 @@ const KIND = /^(Topic|Review) \d+ — /u;
 
 export interface ReleaseProblem {
   issue: number;
+  /** The LeetCode number, the key of the docs `/<num>` short links. */
+  lc: number;
   /** `LC 57 · Insert Interval`. */
   title: string;
   set: string;
   /** `easy` / `medium` / `hard`, the problem's `diff:*` label. */
   difficulty: string;
-  /** The problem's `/<num>` docs short link, once it has a page. */
-  docs?: string;
 }
 
 export interface Release {
@@ -53,15 +55,10 @@ function closedProblems(body: string): ReleaseProblem[] {
   for (const line of body.split("\n")) {
     if (line.startsWith("### ")) closed = line.startsWith("### Closed");
     if (!closed || !line.startsWith("| #")) continue;
-    const [issue, title, set, difficulty, , solution] = line.slice(1, -1).split("|").map((cell) => cell.trim());
-    if (!issue || !title || !set || !difficulty) continue;
-    problems.push({
-      issue: Number(issue.slice(1)),
-      title,
-      set,
-      difficulty,
-      docs: solution?.match(/\[docs\]\(([^)]+)\)/u)?.[1],
-    });
+    const [issue, title, set, difficulty] = line.slice(1, -1).split("|").map((cell) => cell.trim());
+    const lc = title?.match(/^LC (\d+) · /u)?.[1];
+    if (!issue || !title || !lc || !set || !difficulty) continue;
+    problems.push({ issue: Number(issue.slice(1)), lc: Number(lc), title, set, difficulty });
   }
   return problems;
 }