feat: use ocis images from same directory level

[saw-jan]

Description

FEAT: able to use images available at the same directory level as the markdown file in the ocis server.

Requirements:

1. allow to embed images that are stored in the same folder or its subfolders by using the markdown image syntax

same folder - ✔️
subfolders - ❌ (Follow up in next PR)

2. not allowing to embed files from a folder of higher levels

✔️

3. require the whole folder be publicly shared if the public viewer should see the images

✔️

4. if only the markdown file is publicly share the viewer should not be able to access the images

✔️

Test Cases:

• local images (image from current directory level)
• large local images
• multiple small images (if images are large then only one might be visible)
• uploaded image (upload into markdown)
• external image url
• audio/video (doesn't work - not supported by the md parser)

Related Issue

• Part of [feature] embed images #27

Screenshots (if appropriate):

Owner:

Folder Link - Viewer:

MD File link - Editor:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Tests only (no source changes)
• Documentation only (no source changes)
• Maintenance (e.g. dependency updates or tooling)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation updated

[saw-jan]

need caching. Will do a follow up PR

[saw-jan]

This PR will be merged to the main branch which will be v2.0.0.
We have released v1.0.0

@grgprarup @S-Panta I have updated the comments. Please re-check if it works

[S-Panta]

Tried and tested locally. LGTM