feat: Add new agents and skills for Docker, TestLink, and OpenWrt

- Introduced "Docker Build & Test Engineer" agent for building and testing Docker images.
- Added "TestLink Autotest Engineer" agent for generating and verifying autotests from TestLink cases.
- Created "Branch Review Engineer" agent for reviewing branch diffs and proposing improvements.
- Developed "OpenWrt VPN & Network Engineer" agent for designing and implementing OpenWrt networking with VPN.
- Established a structured directory for agents, skills, prompts, instructions, and hooks under `.github/`.
- Implemented detailed skills for branch review processes, including reading code, analyzing improvements, and applying changes.
- Added skills for OpenWrt network discovery, VPN routing, and hardening.
- Created README files for better documentation and navigation of the repository structure.

.github/skills/openwrt-network-discovery/SKILL.md

@@ -0,0 +1,76 @@
+---
+name: openwrt-network-discovery
+description: "Collect and validate OpenWrt network baseline before VPN changes. Use when: openwrt audit, openwrt inventory, собрать сетевой контекст openwrt, before vpn setup, interfaces and routes check, request mcp webhook details."
+argument-hint: "OpenWrt target and goals (device, version, VPN type, tunnel policy)"
+---
+
+# OpenWrt Network Discovery
+
+Build a reliable baseline before any routing or VPN configuration.
+
+## When to Use
+
+- Any OpenWrt VPN setup or migration
+- Split tunneling and policy-based routing requests
+- GeoIP/ASN policy design
+- Cases requiring MCP or webhook integrations
+
+## Procedure
+
+### Step 1 - Gather Environment Facts
+
+Collect from user and system:
+- router model and OpenWrt version
+- package list for VPN stack (`xray`, `sing-box`, `wireguard`, `openvpn`)
+- interface names and network zones
+- WAN uplink type and current default route
+
+### Step 2 - Gather Traffic Policy Requirements
+
+Ask for exact targeting:
+- destination IP list that must use VPN
+- domain-based rules if needed
+- country/GeoIP and ASN-based requirements
+- protocols/ports that must bypass or force tunnel
+
+### Step 3 - Gather DNS Policy
+
+Capture:
+- preferred DNS resolvers for WAN and VPN
+- encrypted DNS requirements (DoH/DoT)
+- fallback policy and leak tolerance
+
+### Step 4 - Request MCP and Webhook Inputs
+
+If user expects integrations, request:
+- MCP servers to use, with server IDs and intended actions
+- webhook endpoints (URL, method, auth type, headers, payload schema)
+- secret storage expectations and rotation policy
+- callback/error handling requirements
+
+Do not design integration details without this data.
+
+### Step 5 - Produce Discovery Summary
+
+Return a structured summary:
+- validated facts
+- missing critical inputs
+- assumptions that require approval
+
+## Output Format
+
+```md
+## Discovery Summary
+
+### Confirmed
+- ...
+
+### Missing
+- ...
+
+### Blocking Questions
+- ...
+
+### Next Step
+- Proceed to `openwrt-vpn-routing` after confirmation.
+```