## Summary
This PR fixes#36255
The image captcha was using random colors which often resulted in poor
contrast against dark backgrounds, making it difficult or impossible for
users to read in dark mode.
## Changes
- Added a custom color palette to the image captcha configuration in
`services/context/captcha.go`
- The palette uses high-contrast colors (bright red, blue, green,
yellow, purple, and dark blue-gray) that provide good visibility in both
light and dark themes
- This improves accessibility and user experience without changing any
existing functionality
## Testing
- Builds successfully
- All existing tests pass
- The color palette is properly supported by the upstream
`gitea.com/go-chi/captcha` library
---
Generated with Claude Code
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Signed-off-by: majiayu000 <1835304752@qq.com>
Co-authored-by: silverwind <me@silverwind.io>
Since `modules/context` has to depend on `models` and many other
packages, it should be moved from `modules/context` to
`services/context` according to design principles. There is no logic
code change on this PR, only move packages.
- Move `code.gitea.io/gitea/modules/context` to
`code.gitea.io/gitea/services/context`
- Move `code.gitea.io/gitea/modules/contexttest` to
`code.gitea.io/gitea/services/contexttest` because of depending on
context
- Move `code.gitea.io/gitea/modules/upload` to
`code.gitea.io/gitea/services/context/upload` because of depending on
context
