chore: add llm instructions

[JP-Ellis]

📝 Summary

Add LLM instructions within .github/instructions/.

🚨 Breaking Changes

🔥 Motivation

This is to help give context to LLMs when/if they contribute to anything on this repo (whether as a standalone agent, or while helping a contributor).

While I would prefer a vendor-agnostic system, I also didn't want to litter this repository with a bunch of AGENTS.md files, and I like the applyTo syntax of the Copilot instruction files.

🔨 Test Plan

🔗 Related issues/PRs

• GitHub docs
• github/awesome-copilot for early inspiration
• AGENTS.md

[Copilot]

Pull Request Overview

This PR adds LLM instruction files within .github/instructions/ to provide context and guidelines for AI assistants contributing to the repository. The instructions use GitHub Copilot's instruction file format with applyTo syntax to target specific file patterns.

• Establishes coding conventions and documentation standards for Python code
• Defines testing guidelines using pytest framework
• Documents the structure and purpose of different package components (core library, V2 legacy, FFI, CLI)

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
.github/instructions/python.instructions.md	General Python coding conventions, documentation standards, and code style guidelines
.github/instructions/python-tests.instructions.md	Testing conventions for pytest-based test files
.github/instructions/pact.instructions.md	Guidelines for the core Pact library structure and key modules
.github/instructions/pact-v2.instructions.md	Instructions for maintaining legacy V2 codebase in maintenance mode
.github/instructions/pact-ffi.instructions.md	Guidelines for low-level FFI bindings package
.github/instructions/pact-cli.instructions.md	Instructions for the CLI wrapper package

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 52%. Comparing base (acd125d) to head (d729f07).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@         Coverage Diff          @@
##           main   #1287   +/-   ##
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  Coverage    52%     52%           
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  Files        32      32           
  Lines      3739    3739           
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  Hits       1966    1966           
  Misses     1773    1773           

Flag	Coverage Δ
tests	52% <ø> (ø)

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