Initial commit: Superpowers plugin v1.0.0

Core skills library as Claude Code plugin:
- Testing skills: TDD, async testing, anti-patterns
- Debugging skills: Systematic debugging, root cause tracing
- Collaboration skills: Brainstorming, planning, code review
- Meta skills: Creating and testing skills

Features:
- SessionStart hook for context injection
- Skills-search tool for discovery
- Commands: /brainstorm, /write-plan, /execute-plan
- Data directory at ~/.superpowers/

hooks/hooks.json

@@ -0,0 +1,21 @@
+{
+  "SessionStart": [
+    {
+      "matcher": "startup|resume",
+      "hooks": [
+        {
+          "type": "command",
+          "command": "mkdir",
+          "args": ["-p", "~/.superpowers"],
+          "description": "Initialize superpowers data directory"
+        },
+        {
+          "type": "json",
+          "hookSpecificOutput": {
+            "additionalContext": "<EXTREMELY_IMPORTANT>\nYou have superpowers.\n\nBefore ANY task, search for relevant skills:\n\n${CLAUDE_PLUGIN_ROOT}/skills/getting-started/skills-search PATTERN\n\n**Skills are mandatory when they exist, not optional.**\n\nFailed searches are logged to: ~/.superpowers/search-log.jsonl\n\n**Skills location**: ${CLAUDE_PLUGIN_ROOT}/skills/\n\nCategories:\n- testing/ - TDD, async testing, anti-patterns\n- debugging/ - Systematic debugging, root cause tracing, verification\n- collaboration/ - Brainstorming, planning, code review, parallel agents\n- meta/ - Creating, testing, and contributing skills\n\n**Critical**: Skills exist and you didn't use them = failed task.\n\n**RIGHT NOW, go read**: ${CLAUDE_PLUGIN_ROOT}/skills/getting-started/SKILL.md\n</EXTREMELY_IMPORTANT>"
+          }
+        }
+      ]
+    }
+  ]
+}