✨ Set up Copilot instructions for ScanBridge repository

[Copilot]

This PR adds comprehensive GitHub Copilot instructions to help AI assistants better understand and contribute to the ScanBridge project. The instructions follow GitHub's best practices for Copilot coding agents and provide detailed context about the project's architecture, coding standards, and development workflows.

What's Added

📝 .github/copilot-instructions.md - A comprehensive guide covering:

• Project Overview: ScanBridge as an Android scanning app using Kotlin, Jetpack Compose, and Material 3 design
• Technology Stack: Detailed information about core technologies (Kotlin, Compose, Gradle, eSCL protocol)
• Development Guidelines: Code formatting with ktlint, project structure, and build commands
• Coding Conventions: GPL-3.0 license headers, package organization, and Material 3 UI patterns
• Testing & CI/CD: Build commands, test structure, and GitHub Actions workflow details
• Domain Knowledge: Scanner-specific context including eSCL/AirScan protocol and paper format handling

Key Benefits

• Better Code Suggestions: Copilot will understand the Android/Kotlin context and suggest appropriate Material 3 components
• Consistent Style: Instructions include ktlint formatting requirements and established coding patterns
• Project-Aware: References to existing documentation (CONTRIBUTING.md, CHANGELOG.md) and project structure
• Scanner Domain Knowledge: Context about eSCL protocol, paper formats, and scanner compatibility considerations

Technical Details

The instructions are structured as clear Markdown sections with code examples showing:

• Proper file headers with GPL-3.0 licensing
• Jetpack Compose component patterns
• Build and test commands
• Package structure and naming conventions

This will help both human developers and AI assistants maintain consistency with the project's established patterns and contribute more effectively to ScanBridge development.

Resolves #[issue_number]

Original prompt

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This section details on the original issue you should resolve

<issue_title>✨ Set up Copilot instructions</issue_title>
<issue_description>Configure instructions for this repository as documented in Best practices for Copilot coding agent in your repository.

</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #89

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[Copilot]

Pull Request Overview

Sets up comprehensive GitHub Copilot instructions to help AI assistants better understand and contribute to the ScanBridge Android scanning app project. This follows GitHub's best practices for Copilot coding agents.

Key changes:

• Adds detailed project context about ScanBridge's Android/Kotlin architecture
• Documents development guidelines, coding conventions, and testing procedures
• Provides scanner-specific domain knowledge for eSCL/AirScan protocol support

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[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 2 changed files in this pull request and generated 2 comments.

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_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 2 changed files in this pull request and generated 1 comment.

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[Copilot]

The ktlint commands reference a local ./ktlint executable, but ktlint is typically installed as a Gradle plugin or standalone tool. Consider clarifying the installation method or using the more common ./gradlew ktlintCheck and ./gradlew ktlintFormat Gradle tasks.

Suggested change

	- Run `./ktlint --editorconfig=./.editorconfig` to check formatting
	- Run `./ktlint --editorconfig=./.editorconfig --format` to fix formatting
	- Run `./gradlew ktlintCheck` to check formatting
	- Run `./gradlew ktlintFormat` to fix formatting