config: update git and herdr settings

[mandaiy]

Summary

• add a shared Git configuration for delta and zdiff3
• link the Git configuration from the bootstrap script
• clean up duplicate ignore entries while keeping Claude Code local settings ignored
• disable the herdr onboarding flow

Why

Keep the Git and herdr defaults reproducible through the dotfiles bootstrap process and remove redundant ignore configuration.

Impact

Running ./init now creates ~/.config/git/config alongside the existing global ignore link. Git uses delta for paging and interactive diffs, and herdr skips onboarding.

Validation

• pre-commit run --all-files
• ./init

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Install delta before configuring it as Git's pager

On a fresh machine following the documented install command (README.md:22-24), or after bootstrapping the Linux image whose package list is at docker/Dockerfile:29-37, no package provides the delta executable. Git lists -p | --paginate in git -h, and with this configuration a paginated git log reports cannot run delta: No such file or directory before falling back, while the intended pager and interactive diff filter remain unavailable. Add the Homebrew git-delta dependency to the supported setup paths or avoid enabling these settings when the executable is absent.

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