Update LICENSE copyright and add AI attribution instructions

[jerrysxie]

This PR applies two org-wide standardisation changes
(ref: OpenDevicePartnership/embedded-rust-template#20):

1. LICENSE – normalise the copyright line to:
   Copyright (c) Open Device Partnership and Contributors

2. .github/copilot-instructions.md – add the Commit Messages and
   AI Attribution sections so every repo carries consistent guidance
   for contributors and AI agents.

[Copilot]

Pull request overview

This PR applies org-wide standardization updates to align this repository with the embedded template guidance referenced in the PR description.

Changes:

• Updates the LICENSE copyright line to the standardized org-wide wording.
• Adds .github/copilot-instructions.md with commit message conventions and required AI attribution guidance for AI-assisted work.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
LICENSE	Normalizes the copyright line to the standardized “Open Device Partnership and Contributors” wording.
.github/copilot-instructions.md	Introduces repo-level guidance for commit message formatting and AI attribution trailers.

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[felipebalbi]

Looks like this one go line endings modified, not a big deal.