fix(github): accept PR-tab URLs (e.g. /files, /commits) in PR URL parser

prisma/migrations/20260925120000_reset_blacklisted_pr_tab_urls/migration.sql

@@ -0,0 +1,6 @@
+UPDATE "Project"
+SET "prDescriptionFetchedAt" = NULL,
+    "prShortDescription" = NULL
+WHERE "prDescriptionFetchedAt" IS NOT NULL
+  AND "prShortDescription" IS NULL
+  AND "prUrl" ~ '^https?://(www\.)?github\.com/[^/]+/[^/]+/pull/[0-9]+/[^/?#]';

src/github/index.test.ts

@@ -57,11 +57,26 @@ function assertEqual<T>(actual: T, expected: T, message: string): void {
     { owner: 'codeday', repo: 'labs-gql', number: 42 },
     'parses owner/repo/number from a pull request URL',
   );
+  assertEqual(
+    parseGithubPullRequestUrl('https://github.com/codeday/labs-gql/pull/42/files'),
+    { owner: 'codeday', repo: 'labs-gql', number: 42 },
+    'parses a PR URL with a trailing tab segment (e.g. /files)',
+  );
+  assertEqual(
+    parseGithubPullRequestUrl('https://github.com/codeday/labs-gql/pull/42/files/diff/abc123'),
+    { owner: 'codeday', repo: 'labs-gql', number: 42 },
+    'parses a PR URL with multiple trailing path segments (deep link)',
+  );
   assertEqual(
     parseGithubPullRequestUrl('https://github.com/codeday/labs-gql/issues/42'),
     null,
     'rejects an issue URL',
   );
+  assertEqual(
+    parseGithubPullRequestUrl('https://github.com/codeday/labs-gql/issues/42/files'),
+    null,
+    'rejects an issue URL with a trailing segment',
+  );
   assertEqual(
     parseGithubPullRequestUrl('https://github.com/codeday/labs-gql'),
     null,

src/github/index.ts

@@ -1,7 +1,7 @@
 import fetch from 'node-fetch';
 import config from '../config';
 
-const GITHUB_URL_RE = /^https?:\/\/(?:www\.)?github\.com\/([^/\s]+)\/([^/\s#?]+?)(?:\.git)?(?:\/(issues|pull)\/(\d+))?\/?(?:[?#].*)?$/i;
+const GITHUB_URL_RE = /^https?:\/\/(?:www\.)?github\.com\/([^/\s]+)\/([^/\s#?]+?)(?:\.git)?(?:\/(issues|pull)\/(\d+)(?:\/[^/?#]+)*?)?\/?(?:[?#].*)?$/i;
 
 export interface GithubRepoRef {
   owner: string;