chore: bump version to 2.2.0 and update documentation

Update version numbers across all packages and documentation:
- Rust Core: 2.1.0 → 2.2.0
- Node SDK: 2.1.0 → 2.2.0
- Python SDK: 2.1.0 → 2.2.0

Update API contract documentation:
- Add maxExecutionTimeMs configuration example
- Add confirmationPolicy configuration example
- Update version references from v2.1.0 to v2.2.0

This release includes:
- Execution timeout protection
- Task leak fixes
- Channel capacity optimization (256 → 2048)
- Duplicate tool call detection
- HITL confirmation policy support
- Full SDK alignment for all new features

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: claude

core/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "a3s-code-core"
-version = "2.1.0"
+version = "2.2.0"
 edition = "2021"
 authors = ["A3S Lab Team"]
 license = "MIT"

sdk/node/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@a3s-lab/code",
-  "version": "2.1.0",
+  "version": "2.2.0",
   "description": "A3S Code - Native Node.js bindings for the coding-agent runtime",
   "main": "index.js",
   "types": "index.d.ts",

sdk/python/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "a3s-code-py"
-version = "2.1.0"
+version = "2.2.0"
 edition = "2021"
 authors = ["A3S Lab Team"]
 license = "MIT"
@@ -12,7 +12,7 @@ name = "a3s_code"
 crate-type = ["cdylib"]
 
 [dependencies]
-a3s-code-core = { version = "2.1.0", path = "../../core", features = ["ahp"] }
+a3s-code-core = { version = "2.2.0", path = "../../core", features = ["ahp"] }
 pyo3 = "0.23"
 tokio = { version = "1.35", features = ["full"] }
 serde_json = "1.0"