feat: add random wall brushing function (needs help with imports)

[ZzCreative]

🎯 Feature: Random Wall Brushing

Problem

Users currently need to click each wall manually. This is time-consuming for users who want to simulate natural contribution patterns.

Solution

Add a random brushing function that allows users to:

• Set density distribution of brushing
• Specify time range for automated brushing
• Let the software randomly brush walls within the parameters

Current Status

• Core algorithm structure implemented in app.go
• Encountered app.go:9:1: missing import path error during local build
• Ready for code review and guidance on import syntax fix

Testing Needed

Once import issue is resolved, will test:

• Density parameter validation
• Time range functionality
• Integration with existing UI

Request for Maintainer Guidance

Could you please help identify the import syntax issue at line 9 of app.go?

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Summary by cubic

Adds random wall brushing with configurable density and date range, plus a UI to preview and apply generated contributions. This helps users simulate natural activity without clicking each wall.

• New Features

  • Backend: GenerateRandomContributions creates contribution days between start/end dates, honoring density, min/max per day, weekend exclusion, and an optional seed. Returns totals and sorted results.
  • Frontend: RandomPaintModal to configure options, generate a preview via Wails, and apply the contributions.

• Bug Fixes

  • Resolve leftover merge markers in app.go imports and add missing imports (math/rand, sort).
  • Regenerate Wails bindings so App.GenerateRandomContributions is available to the frontend.

^{Written for commit c34ab2b. Summary will update automatically on new commits.}

[cubic-dev-ai]

No issues found across 2 files

[zmrlft]

Thank you very much for your contribution, brother. I will review it in a few days. I've been extremely busy recently. Sorry, sorry.