implement MacOS openFile/openFiles events for file associations

[APshenkin]

Description

Implements file association for macOS #1830

MacOs provides two events for cases when single or multiple files are opened.

You can see how it works here.
![Watch the video]

Also important note for documentation is how to specify associated files in Info.plist

        <key>CFBundleDocumentTypes</key>
        <array>
          <dict>
            <key>CFBundleTypeExtensions</key>
            <array>
              <string>wwails</string>
            </array>
            <key>CFBundleTypeName</key>
            <string>Wails Test File</string>
          </dict>
        </array>

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Test repo is available here https://github.com/APshenkin/wails-open-file
PR should be fetched and replace in go.mod should be adjusted

• Windows
• macOS
• Linux

Test Configuration

# Wails
Version  | v2.6.0
Revision | a419721dcdf16da7a4afd92b9ba63b2050229a26
Modified | true

# System
┌─────────────────────────┐
| OS           | MacOS    |
| Version      | 13.5.2   |
| ID           | 22G91    |
| Go Version   | go1.20.2 |
| Platform     | darwin   |
| Architecture | arm64    |
└─────────────────────────┘

# Dependencies
┌─────────────────────────────────────────────────────────────────────────┐
| Dependency                | Package Name | Status    | Version          |
| Xcode command line tools  | N/A          | Installed | 2397             |
| Nodejs                    | N/A          | Installed | 16.15.0          |
| npm                       | N/A          | Installed | 8.19.3           |
| *Xcode                    | N/A          | Installed | 14.3.1 (14E300c) |
| *upx                      | N/A          | Available |                  |
| *nsis                     | N/A          | Available |                  |
└──────────────────────── * - Optional Dependency ────────────────────────┘

Checklist:

• I have updated website/src/pages/changelog.mdx with details of this PR
• My code follows the general coding style of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[APshenkin]

closed as open version with Windows support together #2918