feat: add git/ignore-changelog script

[credfeto]

Add a script git/ignore-changelog that adds CHANGELOG.md to .markdownlintignore across all git repositories found in the current directory.

The script supports a --dry-run / -n flag to preview changes without writing or committing anything.

Prompt: commit and push

[dnyw4l3n13]

Implementation Plan

Files to change

• git/ignore-changelog — new script that iterates over all git repositories in the current directory and adds CHANGELOG.md to .markdownlintignore, committing and pushing the result; supports --dry-run / -n flag to preview without writing
• CHANGELOG.md — add entry for the new script

Approach

Create a POSIX shell script at git/ignore-changelog that uses find (or a glob over $(pwd)/*/) to discover all directories containing a .git entry. For each repo, check whether .markdownlintignore already contains CHANGELOG.md; if not, either append/create it and commit+push (normal mode) or print what would be done without touching the file system (dry-run mode). Output helpers (die/success/info) from the project's shell-script conventions are used for consistent coloured output.

Test strategy

Manual verification: run the script against a set of local test repos in both normal and --dry-run modes; confirm .markdownlintignore is created/updated correctly and that dry-run makes no changes.

Assumptions

• Repositories are immediate subdirectories of the current working directory (not nested deeper).
• Git identity and push access are already configured in each target repo.
• The script should skip push hooks (--no-verify) on the target repos, matching the pattern used by other scripts in this project.

Open questions

None — ready to proceed pending approval.

Note: this implementation is already complete on branch feat/ignore-changelog — PR #707 is open and CI is passing.