Add GitAgent Protocol support (agent.yaml + SOUL.md)

[shreyas-lyzr]

Hi @howl-anderson! 👋

AgentSilex is a great project — transparent, minimal, hackable. Exactly the kind of agent framework the ecosystem needs. This PR proposes adding GitAgent Protocol (GAP) support: a small, open standard for portable AI agents (https://gitagent.sh).

What this adds (nothing else changes):

• agent.yaml — a standard manifest capturing your agent's name, version, model support, runtime limits, skills, and compliance posture
• SOUL.md — AgentSilex's persona and philosophy in the GAP standard format, distilled faithfully from your README

Why this might be useful for AgentSilex:

• Any GAP-compatible runtime (Claude Code, GitClaw, and others) can load and run an AgentSilex-based agent from these files
• Your project becomes listable in the Open GAP Registry — a discoverable index of portable agents
• The manifest makes AgentSilex's multi-model, multi-skill architecture explicit and machine-readable

This is 100% optional to accept — feel free to tweak the files, suggest changes, or close if it's not a fit. The SOUL.md tries to represent AgentSilex's philosophy faithfully (transparency, minimalism, hackability) and nothing in your existing codebase is modified. 🙏

→ Learn more: https://gitagent.sh