opencode: add OAC

opencode/context/core/context-system/navigation.md

@@ -0,0 +1,53 @@
+<!-- Context: core/navigation | Priority: critical | Version: 1.0 | Updated: 2026-02-15 -->
+
+# Context System
+
+**Purpose**: Documentation for the context system architecture and operations
+
+---
+
+## Structure
+
+```
+core/context-system/
+├── navigation.md (this file)
+├── examples/
+│   └── navigation.md
+├── guides/
+│   └── navigation.md
+├── operations/
+│   └── navigation.md
+├── standards/
+│   └── navigation.md
+└── [overview files]
+```
+
+---
+
+## Quick Routes
+
+| Task | Path |
+|------|------|
+| **Understand context system** | `../context-system.md` |
+| **Operations & procedures** | `operations/navigation.md` |
+| **Implementation guides** | `guides/navigation.md` |
+| **Standards & templates** | `standards/navigation.md` |
+| **Examples** | `examples/navigation.md` |
+| **Migrate global → local** | `operations/migrate.md` |
+
+---
+
+## By Type
+
+**Examples** → Working examples of navigation files  
+**Guides** → Step-by-step guides for working with context  
+**Operations** → How to operate and maintain the context system  
+**Standards** → Templates and standards for context files
+
+---
+
+## Related Context
+
+- **Core Navigation** → `../navigation.md`
+- **Core Standards** → `../standards/navigation.md`
+- **Core System** → `../system/navigation.md`