refactor(enrichment): soften blame-link wording + precise category + tighter cap test (#2034)

Final review nits (all non-blocking):
- Render says the file "was most recently touched by" instead of "introduced by"
  a specific line — accurate to the file-level path-history lookup this does.
- Give the commit→PR association call its own endpointCategory
  ("github-commit-pulls") for precise rate attribution (loop-level MAX_LOOKUPS
  still bounds the total).
- Cap test now asserts exactly 12 fetch calls and that files past the probe cap
  (f6..f9) are never queried, pinning the bound.

review-enrichment: 402/402 pass.

Author: nickmopen

review-enrichment/src/analyzers/blame-link.ts

@@ -76,9 +76,10 @@ async function fetchGithubJson<T>(
   signal: AbortSignal | undefined,
   options: Pick<ScanOptions, "analysis" | "diagnostics">,
   subcall: string,
+  endpointCategory: string,
 ): Promise<T | null> {
   const fetchOptions = {
-    endpointCategory: "github-commits",
+    endpointCategory,
     headers,
     signal,
     fetchImpl: fetchFn,
@@ -110,7 +111,9 @@ export async function fetchLatestCommitSha(
   const url =
     `${GITHUB_API}/repos/${encodeURIComponent(owner)}/${encodeURIComponent(repo)}/commits` +
     `?path=${encodeURIComponent(path)}&per_page=1${shaQuery}`;
-  const commits = await fetchGithubJson<CommitListItem[]>(url, headers, fetchFn, signal, options, "github-commits");
+  const commits = await fetchGithubJson<CommitListItem[]>(
+    url, headers, fetchFn, signal, options, "github-commits", "github-commits",
+  );
   const sha = Array.isArray(commits) ? commits[0]?.sha : undefined;
   return typeof sha === "string" && sha ? sha : null;
 }
@@ -126,7 +129,9 @@ export async function fetchPrForCommit(
   options: Pick<ScanOptions, "analysis" | "diagnostics">,
 ): Promise<number | null> {
   const url = `${GITHUB_API}/repos/${encodeURIComponent(owner)}/${encodeURIComponent(repo)}/commits/${encodeURIComponent(sha)}/pulls`;
-  const pulls = await fetchGithubJson<AssociatedPr[]>(url, headers, fetchFn, signal, options, "github-commit-pulls");
+  const pulls = await fetchGithubJson<AssociatedPr[]>(
+    url, headers, fetchFn, signal, options, "github-commit-pulls", "github-commit-pulls",
+  );
   const number = Array.isArray(pulls) ? pulls[0]?.number : undefined;
   return typeof number === "number" ? number : null;
 }

review-enrichment/src/analyzers/registry.ts

@@ -470,7 +470,7 @@ export const ANALYZER_DESCRIPTORS = [
               ? `commit ${helpers.safeCodeSpan(item.introducedByShaPrefix)}`
               : "an unknown prior change";
         lines.push(
-          `- ${helpers.safeCodeSpan(item.file)} (old line ${item.line}) was most recently introduced by ${origin}`,
+          `- ${helpers.safeCodeSpan(item.file)} (around old line ${item.line}) was most recently touched by ${origin}`,
         );
       }
       return lines;

review-enrichment/test/blame-link.test.ts

@@ -100,14 +100,26 @@ test("scanBlameLink: pure-addition and added files are skipped (nothing to blame
   assert.deepEqual(findings, []);
 });
 
-test("scanBlameLink: caps the number of files probed", async () => {
+test("scanBlameLink: caps probed files and total lookups, leaving later files untouched", async () => {
   const files = Array.from({ length: 10 }, (_, i) => ({
     path: `src/f${i}.ts`,
     status: "modified",
     patch: modifyPatch(i + 1),
   }));
-  const findings = await scanBlameLink(req(files), routedFetch({ commitSha: "abcdef1234567890", prNumber: 9 }));
+  let calls = 0;
+  const probedPaths = new Set();
+  const countingFetch = async (url) => {
+    calls += 1;
+    const path = new URL(url).searchParams.get("path");
+    if (path) probedPaths.add(path);
+    if (url.includes("/pulls")) return jsonResponse([{ number: 9 }]);
+    if (url.includes("/commits?")) return jsonResponse([{ sha: "abcdef1234567890" }]);
+    return jsonResponse([], 404);
+  };
+  const findings = await scanBlameLink(req(files), countingFetch);
   assert.equal(findings.length, 6); // MAX_FILES_PROBED
+  assert.equal(calls, 12); // 6 files × (1 commit-list + 1 pulls) = MAX_LOOKUPS; not one more
+  assert.deepEqual([...probedPaths].sort(), ["src/f0.ts", "src/f1.ts", "src/f2.ts", "src/f3.ts", "src/f4.ts", "src/f5.ts"]); // f6..f9 never probed
 });
 
 test("scanBlameLink: no GitHub token → skipped (no finding, no throw)", async () => {