feat: add pull request skill workflow

plugins/engineering-playbook/skills/creating-skills/SKILL.md

@@ -0,0 +1,17 @@
+---
+name: creating-skills
+description: >-
+  Creates, edits, and maintains agent skills and their referenced resources.
+  Use when creating a new skill, editing SKILL.md, changing skill frontmatter,
+  or modifying files referenced by a skill such as references, scripts, or
+  assets.
+---
+
+## Source
+
+Before creating or editing a skill or any file referenced by a skill, read:
+
+https://platform.claude.com/docs/en/agents-and-tools/agent-skills/best-practices
+
+Follow that guidance strictly. If the page cannot be read, report the blocker
+before editing unless the user explicitly says to continue.

plugins/engineering-playbook/skills/development/SKILL.md

@@ -16,6 +16,9 @@ source of truth.
 ## Load First
 
 - Read `coding-standards`.
+- Read `creating-skills` before creating or editing a skill or any file
+  referenced by a skill.
+- Read `pull-request` before creating or preparing a pull request.
 - Read `laravel-standards` before touching code that affects a
   Laravel application.
 
@@ -71,20 +74,9 @@ format.
 
 ## Pull Request Gate
 
-Create a pull request only when all of these are true:
-
-- implementation satisfies the request
-- `Blocker` and `Normal` review findings are fixed
-- unresolved `Low` findings have been shown to the user
-- Mago passes without warnings or errors
-- relevant tests pass
-- the commit message and pull request title use Conventional Commits
-- the pull request description is one short high-level plain-English paragraph
-  without technical details
-- the pull request description includes `Closes #<issue-number>` when the work
-  resolves a GitHub issue, and does not mention any issue the pull request does
-  not resolve
-
-If any gate is not clean, do not create the pull request. Report what is done,
-what failed, the commands run, and the question or decision needed from the
-user.
+Create a pull request only after the implementation is done, required review
+findings are handled, Mago is clean, and relevant tests pass. Otherwise report
+the blocker instead of opening the PR.
+
+When this gate is clean, follow `pull-request` to write the title and
+description.

plugins/engineering-playbook/skills/pull-request/SKILL.md

@@ -0,0 +1,22 @@
+---
+name: pull-request
+description: >-
+  Writes and creates small GitHub pull requests with Conventional Commit titles,
+  concise descriptions, and issue-closing references. Use when opening,
+  drafting, publishing, or preparing a pull request.
+---
+
+# Pull Request
+
+## Workflow
+
+1. Use a short Conventional Commit title. Do not add an issue number to the title
+   unless the repository requires it.
+2. Write one high-level plain-English paragraph for the body. Leave out
+   implementation details, test logs, file lists, checklists, and review notes
+   unless a repository template requires them.
+3. When the PR resolves a GitHub issue, include `Closes #<issue-number>` in the
+   body. Use `Fixes #<issue-number>` only when that wording better matches the
+   work. Do not mention issues the PR does not resolve.
+4. After creating the PR, verify the title and body. If a required issue-closing
+   reference is missing, update the PR body immediately.