feat: Add feature specifications and update documentation structure

Author: tercel

README.md

@@ -911,6 +911,18 @@ Development guide: see [Adapter Development Guide](./docs/guides/adapter-develop
 | [Registry API](./docs/api/registry-api.md) | Registry API |
 | [Executor API](./docs/api/executor-api.md) | Executor API |
 
+### Feature Specifications
+
+| Document | Description |
+|------|------|
+| [ACL System](./docs/features/acl-system.md) | Pattern-based Access Control List with first-match-wins evaluation |
+| [Core Executor](./docs/features/core-executor.md) | Core execution engine with 10-step pipeline |
+| [Decorator & YAML Bindings](./docs/features/decorator-bindings.md) | `@module` decorator and YAML-based module creation |
+| [Middleware System](./docs/features/middleware-system.md) | Composable middleware pipeline with onion execution model |
+| [Observability](./docs/features/observability.md) | Distributed tracing, metrics, and structured logging |
+| [Registry System](./docs/features/registry-system.md) | Module discovery, registration, and querying |
+| [Schema System](./docs/features/schema-system.md) | Schema loading, validation, `$ref` resolution, and export |
+
 ### Usage Guides
 
 | Document | Description |

SCOPE.md

@@ -210,6 +210,7 @@ apcore/
     ├── concepts.md           # Core concepts
     ├── architecture.md       # Internal architecture
     ├── api/                  # API reference
+    ├── features/             # Feature specifications
     ├── guides/               # Usage guides
     └── spec/                 # Framework specification
 ```

docs/README.md

@@ -2,7 +2,7 @@
 
 > Complete technical documentation for the apcore (AI-Perceivable Core) framework.
 
-This directory contains all technical documentation for apcore, covering core concepts, architecture design, API references, usage guides, and framework specifications.
+This directory contains all technical documentation for apcore, covering core concepts, architecture design, feature specifications, API references, usage guides, and framework specifications.
 For a project overview and quick start, see the [main README](../README.md).
 For language SDK implementations, see [Implementations](../README.md#implementations).
 
@@ -18,6 +18,14 @@ docs/
 │   ├── context-object.md              ← Context execution context
 │   ├── registry-api.md                ← Registry center
 │   └── executor-api.md                ← Executor
+├── features/                          ← Feature specifications (for SDK implementors)
+│   ├── acl-system.md                  ← Access Control System
+│   ├── core-executor.md               ← Core Execution Engine
+│   ├── decorator-bindings.md          ← Decorator and YAML Bindings
+│   ├── middleware-system.md           ← Middleware System
+│   ├── observability.md               ← Observability System
+│   ├── registry-system.md             ← Module Registry and Discovery System
+│   └── schema-system.md              ← Schema System
 ├── guides/                            ← Usage guides (7 articles)
 │   ├── creating-modules.md            ← Getting started with module creation
 │   ├── schema-definition.md           ← Schema definition in detail
@@ -54,6 +62,20 @@ Core interface definitions for the module system, including complete API documen
 | [Registry API](./api/registry-api.md) | Module registry center API |
 | [Executor API](./api/executor-api.md) | Module executor API |
 
+### [Feature Specifications](./features/)
+
+Implementation-ready feature specifications for SDK developers. Each document defines a specific subsystem's behavior, interfaces, acceptance criteria, and test scenarios.
+
+| Feature Spec | Description |
+|--------------|-------------|
+| [ACL System](./features/acl-system.md) | Pattern-based Access Control List with first-match-wins evaluation |
+| [Core Executor](./features/core-executor.md) | Central orchestration engine with 10-step execution pipeline |
+| [Decorator & YAML Bindings](./features/decorator-bindings.md) | `@module` decorator and YAML-based declarative module creation |
+| [Middleware System](./features/middleware-system.md) | Composable middleware pipeline with onion execution model |
+| [Observability](./features/observability.md) | Distributed tracing, metrics collection, and structured logging |
+| [Registry System](./features/registry-system.md) | Module discovery, registration, and querying with 8-step pipeline |
+| [Schema System](./features/schema-system.md) | Schema loading, validation, `$ref` resolution, and LLM export |
+
 ### [Usage Guides](./guides/)
 
 Practical tutorials covering everything from creating your first module to middleware development, ACL configuration, and cross-language development. 7 guides in total, covering the full path from beginner to advanced.

mkdocs.yml

@@ -66,6 +66,14 @@ nav:
       - Context Object: api/context-object.md
       - Registry API: api/registry-api.md
       - Executor API: api/executor-api.md
+  - Feature Specifications:
+      - ACL System: features/acl-system.md
+      - Core Executor: features/core-executor.md
+      - Decorator & YAML Bindings: features/decorator-bindings.md
+      - Middleware System: features/middleware-system.md
+      - Observability: features/observability.md
+      - Registry System: features/registry-system.md
+      - Schema System: features/schema-system.md
   - User Guides:
       - Overview: guides/README.md
       - Creating Modules: guides/creating-modules.md