feat: action service

[YuanYuYuan]

Add Full ROS 2 Actions Support to ros-z

This PR introduces complete ROS 2 Actions support to ros-z, enabling goal-driven, long-running tasks with feedback and cancellation. It includes full client/server APIs, code generation, testing infrastructure, and example applications.

Highlights

Core Implementation

• Added a new action module (7 submodules) defining the full client/server architecture.
• Implements async goal submission, feedback streaming, and safe compile-time transitions using the type-state pattern.
• Added internal driver, message types, and macros for simplified action definition.

Code Generation

• Enhanced ros-z-codegen to generate action types (Goal, Result, Feedback) and inject modules into package namespaces.
• Supports ROS 2 action hash interoperability.

Testing Infrastructure

• Reworked test setup for isolated per-test Zenoh routers, enabling fully parallel and interference-free tests.
• Added 11 new test modules with comprehensive coverage: goal lifecycle, concurrency, cancellation, and interop.

Examples

• Added Fibonacci action client and server demos demonstrating incremental computation, feedback streaming, and cancellation.

Graph API

• Added graph methods for discovering action servers and clients by node.

Other Improvements

• Cleaned up legacy code in wait_set.rs and improved subscription safety.
• Updated dependencies (action_msgs, unique_identifier_msgs, tokio-util).

Architecture Notes

• Type-state safety: Enforces correct goal lifecycle transitions at compile time.
• Async-first: Implements non-blocking APIs with background drivers managing ROS 2 action protocols.
• Interoperable: Fully compatible with ROS 2 standard messages and services.