[FEATURE] Add full service for file uploads

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

I use Claude Code regularly and I expect there to be full service for file uploads. Instead, what I see is prioritization and exclusivity for image file uploads only. I'm on the Android app.

Proposed Solution

This means allowing any and all industry standard and reasonably expected file types such as markdown, pdf, zip, python, etc.

Alternative Solutions

Currently I work around this by taking pictures of any code or document files I want to add to my session, and then adding them that way.

Priority

High - Significant impact on productivity

Feature Category

File operations

Use Case Example

Example would be that I'm working on a session for creating an HTML file:

1. Instead of being able to just upload a reference HTML file, I have to screenshot it.
2. Then I have to upload this screenshot, sometimes in multiple parts.

Additional Context

_No response_