ci(infra): clarify early PR auto-close guidance (#38090)

External contributors now get clearer guidance when the issue-link check
closes a PR before maintainer assignment. The auto-close copy
distinguishes the intended flow from the recovery path for PRs that were
opened early.

.github/workflows/require_issue_link.yml

@@ -381,10 +381,10 @@ jobs:
                 marker,
                 '**This PR has been automatically closed** because it does not link to an approved issue.',
                 '',
-                'All external contributions must reference an approved issue or discussion. Please:',
+                'All external contributions must reference an approved issue or discussion. Opening a PR before maintainer approval and assignment is discouraged. Please:',
                 '1. Find or [open an issue](https://github.com/' + owner + '/' + repo + '/issues/new/choose) describing the change',
-                '2. Wait for a maintainer to approve and assign you',
-                '3. Add `Fixes #<issue_number>`, `Closes #<issue_number>`, or `Resolves #<issue_number>` to your PR description and the PR will be reopened automatically',
+                '2. Wait for a maintainer to approve the approach and assign you',
+                '3. After assignment, open a PR. If this PR was opened early, add `Fixes #<issue_number>`, `Closes #<issue_number>`, or `Resolves #<issue_number>` to the description and it can be reopened automatically',
                 '',
                 '*Maintainers: reopen this PR or remove the `missing-issue-link` label to bypass this check.*',
               ];
@@ -393,9 +393,9 @@ jobs:
                 marker,
                 '**This PR has been automatically closed** because you are not assigned to the linked issue.',
                 '',
-                'Opening a PR is **not** an indication that it will be accepted. This process exists so maintainers can confirm a change is aligned with the project direction *before* you invest time implementing it. Please:',
+                'Opening a PR before assignment is discouraged and is **not** an indication that it will be accepted. This process exists so maintainers can confirm a change is aligned with the project direction *before* contributors invest time implementing it. Please:',
                 '1. Comment on the linked issue explaining the approach you would like to take and why — include enough detail for a maintainer to evaluate the design. Do **not** post a drive-by "please assign me" comment with no substance; those will be ignored.',
-                '2. Wait for a maintainer to assign you. Once assigned, your PR will be reopened automatically.',
+                '2. Wait for a maintainer to approve the approach and assign you. Once assigned, this PR can be reopened automatically.',
                 '',
                 '*Maintainers: reopen this PR or remove the `missing-issue-link` label to bypass this check.*',
               ];