Remove obsolete sharing-skills skill

The contribution workflow is now via standard GitHub PR process,
not a dedicated skill. The skill was documenting an old workflow
that no longer applies.

skills/sharing-skills/SKILL.md

@@ -1,194 +0,0 @@
----
-name: sharing-skills
-description: Use when you've developed a broadly useful skill and want to contribute it upstream via pull request - guides process of branching, committing, pushing, and creating PR to contribute skills back to upstream repository
----
-
-# Sharing Skills
-
-## Overview
-
-Contribute skills from your local branch back to the upstream repository.
-
-**Workflow:** Branch → Edit/Create skill → Commit → Push → PR
-
-## When to Share
-
-**Share when:**
-- Skill applies broadly (not project-specific)
-- Pattern/technique others would benefit from
-- Well-tested and documented
-- Follows writing-skills guidelines
-
-**Keep personal when:**
-- Project-specific or organization-specific
-- Experimental or unstable
-- Contains sensitive information
-- Too narrow/niche for general use
-
-## Prerequisites
-
-- `gh` CLI installed and authenticated
-- Working directory is `~/.config/superpowers/skills/` (your local clone)
-- **REQUIRED:** Skill has been tested using writing-skills TDD process
-
-## Sharing Workflow
-
-### 1. Ensure You're on Main and Synced
-
-```bash
-cd ~/.config/superpowers/skills/
-git checkout main
-git pull upstream main
-git push origin main  # Push to your fork
-```
-
-### 2. Create Feature Branch
-
-```bash
-# Branch name: add-skillname-skill
-skill_name="your-skill-name"
-git checkout -b "add-${skill_name}-skill"
-```
-
-### 3. Create or Edit Skill
-
-```bash
-# Work on your skill in skills/
-# Create new skill or edit existing one
-# Skill should be in skills/category/skill-name/SKILL.md
-```
-
-### 4. Commit Changes
-
-```bash
-# Add and commit
-git add skills/your-skill-name/
-git commit -m "Add ${skill_name} skill
-
-$(cat <<'EOF'
-Brief description of what this skill does and why it's useful.
-
-Tested with: [describe testing approach]
-EOF
-)"
-```
-
-### 5. Push to Your Fork
-
-```bash
-git push -u origin "add-${skill_name}-skill"
-```
-
-### 6. Create Pull Request
-
-```bash
-# Create PR to upstream using gh CLI
-gh pr create \
-  --repo upstream-org/upstream-repo \
-  --title "Add ${skill_name} skill" \
-  --body "$(cat <<'EOF'
-## Summary
-Brief description of the skill and what problem it solves.
-
-## Testing
-Describe how you tested this skill (pressure scenarios, baseline tests, etc.).
-
-## Context
-Any additional context about why this skill is needed and how it should be used.
-EOF
-)"
-```
-
-## Complete Example
-
-Here's a complete example of sharing a skill called "async-patterns":
-
-```bash
-# 1. Sync with upstream
-cd ~/.config/superpowers/skills/
-git checkout main
-git pull upstream main
-git push origin main
-
-# 2. Create branch
-git checkout -b "add-async-patterns-skill"
-
-# 3. Create/edit the skill
-# (Work on skills/async-patterns/SKILL.md)
-
-# 4. Commit
-git add skills/async-patterns/
-git commit -m "Add async-patterns skill
-
-Patterns for handling asynchronous operations in tests and application code.
-
-Tested with: Multiple pressure scenarios testing agent compliance."
-
-# 5. Push
-git push -u origin "add-async-patterns-skill"
-
-# 6. Create PR
-gh pr create \
-  --repo upstream-org/upstream-repo \
-  --title "Add async-patterns skill" \
-  --body "## Summary
-Patterns for handling asynchronous operations correctly in tests and application code.
-
-## Testing
-Tested with multiple application scenarios. Agents successfully apply patterns to new code.
-
-## Context
-Addresses common async pitfalls like race conditions, improper error handling, and timing issues."
-```
-
-## After PR is Merged
-
-Once your PR is merged:
-
-1. Sync your local main branch:
-```bash
-cd ~/.config/superpowers/skills/
-git checkout main
-git pull upstream main
-git push origin main
-```
-
-2. Delete the feature branch:
-```bash
-git branch -d "add-${skill_name}-skill"
-git push origin --delete "add-${skill_name}-skill"
-```
-
-## Troubleshooting
-
-**"gh: command not found"**
-- Install GitHub CLI: https://cli.github.com/
-- Authenticate: `gh auth login`
-
-**"Permission denied (publickey)"**
-- Check SSH keys: `gh auth status`
-- Set up SSH: https://docs.github.com/en/authentication
-
-**"Skill already exists"**
-- You're creating a modified version
-- Consider different skill name or coordinate with the skill's maintainer
-
-**PR merge conflicts**
-- Rebase on latest upstream: `git fetch upstream && git rebase upstream/main`
-- Resolve conflicts
-- Force push: `git push -f origin your-branch`
-
-## Multi-Skill Contributions
-
-**Do NOT batch multiple skills in one PR.**
-
-Each skill should:
-- Have its own feature branch
-- Have its own PR
-- Be independently reviewable
-
-**Why?** Individual skills can be reviewed, iterated, and merged independently.
-
-## Related Skills
-
-- **writing-skills** - REQUIRED: How to create well-tested skills before sharing