fix(pr-skill): move changelog phase after PR creation (#934)

## Summary

The changelog update phase needs the PR number to create proper links
(e.g. `[#123]`) in entries. Previously, changelogs were updated in Phase
4 before the PR was created in Phase 5, making it impossible to include
the PR link.

- Swap Phase 4 (changelogs) and Phase 5 (PR creation) so the PR number
is available when writing changelog entries
- Add explicit emphasis on key `updating-changelogs.md` rules that were
being missed: consumer-perspective thinking, combining like changes,
splitting disparate changes, and linking the PR number

## Testing

This is a docs-only change to a Claude Code skill definition. Verified
the final file reads correctly with proper phase ordering and emphasis.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Docs-only change to the PR-creation skill workflow; minimal risk
beyond process/labeling instructions potentially being followed
incorrectly.
> 
> **Overview**
> Reorders the `pr` Claude skill workflow so the PR is created in Phase
4 before changelog updates, ensuring the PR number is available for
changelog links.
> 
> Adds explicit Phase 5 guidance to either apply a `no-changelog` label
for non-consumer-facing changes or update changelogs with emphasized
rules (consumer-focused wording, combining/splitting entries, and
linking the PR) before presenting results.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
d817845. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: sirtimid

.claude/skills/pr/SKILL.md

@@ -107,13 +107,7 @@ Otherwise, after all launched subagents complete:
    - Abort
 4. If there are no blockers, briefly summarize the findings and proceed.
 
-## Phase 4: Update changelogs
-
-**MANDATORY — DO NOT SKIP.** Each PR must update changelogs for all packages with consumer-facing changes.
-Read the instructions in [`docs/contributing/updating-changelogs.md`](../../../docs/contributing/updating-changelogs.md) and follow them to the letter.
-Commit the changes to the current branch with the commit message "docs: Update changelogs" before creating the PR.
-
-## Phase 5: Create the PR
+## Phase 4: Create the PR
 
 1. Run `gh pr create` to create a pull request. The PR body should include:
 
@@ -123,4 +117,24 @@ Commit the changes to the current branch with the commit message "docs: Update c
 
    **If this is a stacked PR**, add `--draft` to create it as a draft PR.
 
-2. Return the PR URL and any relevant information. If a review was performed, include the review summary.
+2. Note the PR number from the created PR URL — it is needed for changelog entries. Proceed to Phase 5 before presenting results to the user.
+
+## Phase 5: Update changelogs
+
+**MANDATORY — DO NOT SKIP.** Analyze the diff and determine whether any changes are consumer-facing (i.e., affect the behavior or API of a published or private package).
+
+- **If there are NO consumer-facing changes** (e.g., docs-only, CI, tooling, skill definitions, dev scripts): add the `no-changelog` label to the PR via `gh pr edit <number> --add-label no-changelog` and skip the rest of this phase.
+- **If there ARE consumer-facing changes**: update changelogs as described below.
+
+Read the instructions in [`docs/contributing/updating-changelogs.md`](../../../docs/contributing/updating-changelogs.md) and follow them **to the letter**. In particular:
+
+- **Think from the consumer's perspective.** A changelog is not a git history. For each affected package, ask: "What changed for someone who depends on this package?" Describe changes in natural language; do not simply reuse commit messages.
+- **Combine like changes.** If multiple commits contribute to a single logical change within one package, write one changelog entry — not one per commit.
+- **Split disparate changes.** If one commit touches unrelated concerns in a single package, write separate entries.
+- **Link the PR.** Use the PR number from Phase 4 in each entry (e.g. `([#123](https://github.com/.../pull/123))`).
+
+Commit the changelog updates to the current branch with the message "docs: Update changelogs" and push.
+
+## Done
+
+Present the PR URL and any relevant information to the user. If a review was performed, include the review summary.