feat: complete OpenCode plugin support with hooks, tools, and commands

Major OpenCode integration overhaul:

- llms.txt: Comprehensive OpenCode documentation for LLMs (642 lines)
- .opencode/plugins/ecc-hooks.ts: All Claude Code hooks translated to OpenCode's plugin system
- .opencode/tools/*.ts: 3 custom tools (run-tests, check-coverage, security-audit)
- .opencode/commands/*.md: All 24 commands in OpenCode format
- .opencode/package.json: npm package structure for opencode-ecc
- .opencode/index.ts: Main plugin entry point

- Delete incorrect LIMITATIONS.md (hooks ARE supported via plugins)
- Rewrite MIGRATION.md with correct hook event mapping
- Update README.md OpenCode section to show full feature parity

OpenCode has 20+ events vs Claude Code's 3 phases:
- PreToolUse → tool.execute.before
- PostToolUse → tool.execute.after
- Stop → session.idle
- SessionStart → session.created
- SessionEnd → session.deleted
- Plus: file.edited, file.watcher.updated, permission.asked, todo.updated

- 12 agents: Full parity
- 24 commands: Full parity (+1 from original 23)
- 16 skills: Full parity
- Hooks: OpenCode has MORE (20+ events vs 3 phases)
- Custom Tools: 3 native OpenCode tools

The OpenCode configuration can now be:
1. Used directly: cd everything-claude-code && opencode
2. Installed via npm: npm install opencode-ecc

.opencode/commands/skill-create.md

@@ -0,0 +1,117 @@
+---
+description: Generate skills from git history analysis
+agent: build
+---
+
+# Skill Create Command
+
+Analyze git history to generate Claude Code skills: $ARGUMENTS
+
+## Your Task
+
+1. **Analyze commits** - Pattern recognition from history
+2. **Extract patterns** - Common practices and conventions
+3. **Generate SKILL.md** - Structured skill documentation
+4. **Create instincts** - For continuous-learning-v2
+
+## Analysis Process
+
+### Step 1: Gather Commit Data
+```bash
+# Recent commits
+git log --oneline -100
+
+# Commits by file type
+git log --name-only --pretty=format: | sort | uniq -c | sort -rn
+
+# Most changed files
+git log --pretty=format: --name-only | sort | uniq -c | sort -rn | head -20
+```
+
+### Step 2: Identify Patterns
+
+**Commit Message Patterns**:
+- Common prefixes (feat, fix, refactor)
+- Naming conventions
+- Co-author patterns
+
+**Code Patterns**:
+- File structure conventions
+- Import organization
+- Error handling approaches
+
+**Review Patterns**:
+- Common review feedback
+- Recurring fix types
+- Quality gates
+
+### Step 3: Generate SKILL.md
+
+```markdown
+# [Skill Name]
+
+## Overview
+[What this skill teaches]
+
+## Patterns
+
+### Pattern 1: [Name]
+- When to use
+- Implementation
+- Example
+
+### Pattern 2: [Name]
+- When to use
+- Implementation
+- Example
+
+## Best Practices
+
+1. [Practice 1]
+2. [Practice 2]
+3. [Practice 3]
+
+## Common Mistakes
+
+1. [Mistake 1] - How to avoid
+2. [Mistake 2] - How to avoid
+
+## Examples
+
+### Good Example
+```[language]
+// Code example
+```
+
+### Anti-pattern
+```[language]
+// What not to do
+```
+```
+
+### Step 4: Generate Instincts
+
+For continuous-learning-v2:
+
+```json
+{
+  "instincts": [
+    {
+      "trigger": "[situation]",
+      "action": "[response]",
+      "confidence": 0.8,
+      "source": "git-history-analysis"
+    }
+  ]
+}
+```
+
+## Output
+
+Creates:
+- `skills/[name]/SKILL.md` - Skill documentation
+- `skills/[name]/instincts.json` - Instinct collection
+
+---
+
+**TIP**: Run `/skill-create --instincts` to also generate instincts for continuous learning.