feat: add use_skill_implement_issue()

[Copilot]

Adds use_skill_implement_issue(), the single-call installer for the implement-issue skill, consistent with the pattern established by use_skill_document() and use_skill_tdd_workflow().

Changes

• R/use_skill_implement_issue.R — new exported function; delegates entirely to .use_skill("implement-issue", ...) and returns the installed path invisibly
• inst/templates/skills/implement-issue/SKILL.md — verbatim copy of .github/skills/implement-issue/SKILL.md (no whisker variables)
• man/use_skill_implement_issue.Rd — generated docs
• tests/testthat/test-use_skill_implement_issue.R — verifies correct install path and invisible return

Usage

use_skill_implement_issue()
#> ✔ Writing '.github/skills/implement-issue/SKILL.md'

Original prompt

---

This section details on the original issue you should resolve

<issue_title>feat: use_skill_implement_issue()</issue_title>
<issue_description>## Summary

As a package developer, in order to give AI agents accurate end-to-end
guidance for implementing GitHub issues in my package, I would like to
install a pkgskills implement-issue skill with a single function call.

Proposed signature

use_skill_implement_issue(
  target_dir = ".github",
  use_skills_subdir = TRUE,
  overwrite = TRUE,
  open = rlang::is_interactive()
)

Arguments

All arguments for use_skill_implement_issue() are already defined in
@R/aaa-shared_params.R.

• target_dir (character(1)) — Directory where the skill will be installed,
  relative to the project root. Defaults to ".github".
• use_skills_subdir (logical(1)) — Whether to place the implement-issue
  folder under a skills subdirectory of target_dir. Defaults to TRUE,
  producing .github/skills/implement-issue/SKILL.md.
• overwrite (logical(1)) — Whether to overwrite an existing skill file.
  Defaults to TRUE.
• open (logical(1)) — Whether to open the installed skill file in the
  editor after creation. Defaults to rlang::is_interactive().

Returns the path to the installed skill file, invisibly (following the
usethis convention and the convention in use_skill_create_issue()).

Behavior

• Validates all arguments using stbl (following the r-code skill
  conventions). Arguments only need to be validated once; things passed to
  .use_skill() without modification should be validated there.
• Calls .use_skill() to install the skill.
• Returns the installed skill file path invisibly.

Under the hood, use_skill_implement_issue() delegates to .use_skill():

.use_skill(
  "implement-issue",
  target_dir = target_dir,
  use_skills_subdir = use_skills_subdir,
  overwrite = overwrite,
  open = open
)

Details

• Create inst/templates/skills/implement-issue/SKILL.md: a copy of
  .github/skills/implement-issue/SKILL.md. The file has no whisker template
  variables.
• Create R/use_skill_implement_issue.R containing
  use_skill_implement_issue().

References

• use_skill_document() in @R/use_skill_document.R — model for this function;
  use_skill_implement_issue() has the same structure but without the
  aaa-shared_params.R bootstrap step.
• .use_skill() in @R/use_skill.R — core implementation for installing skills.
• Existing .github/skills/implement-issue/SKILL.md — source for the template.
  EOF 2>&1</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes feat: use_skill_implement_issue() #18

---

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[jonthegeek]

@copilot Resolve conflicts in NAMESPACE and NEWS.md to allow this to merge to main.

The tests in tests/testthat/test-use_skill_implement_issue.R should reference "(#18)" at the end of the test description (see other test files for examples).

Update NEWS.md to reference #18, not #12, since this PR addresses issue #18, not #12.

[Copilot]

@copilot Resolve conflicts in NAMESPACE and NEWS.md to allow this to merge to main.

The tests in tests/testthat/test-use_skill_implement_issue.R should reference "(#18)" at the ...

Done in df95c0e — merged main to resolve the NAMESPACE and NEWS.md conflicts, updated the NEWS.md bullet to reference #18, and added (#18) to both test descriptions.

[jonthegeek]

Strong work!