[FEATURE] Support image standard markdown in agent mode and chat mode

[edenreich]

Summary

When the agent is requested to read a comment in Github it may contain image syntax, those should be supported in addition to @ sign.

Maybe we should actually deprecate the @ sign for images because in most software it used to mention something and this might collide with other conventions.

A markdown image syntax is like this:

![Screenshot of a comment on a GitHub issue showing an image, added in the Markdown, of an Octocat smiling and raising a tentacle.](https://myoctocat.com/assets/images/base-octocat.svg)

The goal is that if a vision mode on github action is being asked to check a screenshot, it will be able to read and understand the images.

Acceptance Criterias

• Image markdown syntax is supported
• agent or chat mode parsing those embedding and attaching them to the prompt properly, the prompt itself is getting replaced with tokens
• Documentation is adjusted
• It's tested

[edenreich]

@claude Can you work on this?

[claude]

Claude finished @edenreich's task —— View job • claude/issue-284-20251129-1504 • Create PR ➔

---

Image markdown support completed ✅

Summary

I've successfully implemented support for standard markdown image syntax in both agent and chat modes. The implementation supports both image URLs and local file paths while maintaining backward compatibility with the existing @filename syntax.

Changes Made

Core Implementation:

• ✅ Added ReadImageFromURL() method to fetch and encode images from HTTP/HTTPS URLs
• ✅ Added IsImageURL() method to validate image URLs
• ✅ Updated expandFileReferences() to parse markdown image syntax: ![](url or path)
• ✅ Support for both remote URLs and local file paths in markdown syntax
• ✅ Images are properly embedded as base64 and replaced with [Image: ...] tokens in prompts
• ✅ Preserved @filename syntax for backward compatibility

Testing:

• ✅ Added comprehensive unit tests for ImageService (URL validation, fetching, error handling)
• ✅ Added tests for markdown image parsing in chat message processor
• ✅ All tests pass (including existing tests)
• ✅ Code formatted and vetted

Documentation:

• ✅ Updated README.md with markdown image syntax examples
• ✅ Added ImageService to Taskfile.yml for mock generation
• ✅ Documented both URL and file path usage

Usage Examples

# Markdown syntax with URL
infer agent "Analyze this diagram ![](https://example.com/diagram.png)"

# Markdown syntax with local file
infer agent "Review this screenshot ![](./screenshots/error.png)"

# Legacy @ syntax (still supported)
infer agent "Check @screenshot.png for issues"

# Mix both syntaxes
infer agent "Compare ![](https://example.com/design.png) with @local-design.png"

Acceptance Criteria Status

• ✅ Image markdown syntax is supported
• ✅ Agent and chat mode parse and embed images properly, replacing them with tokens
• ✅ Documentation is adjusted
• ✅ It's tested

---

[ig-semantic-release-bot]

🎉 This issue has been resolved in version 0.72.0 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀