docs: add Extensions section with zshow.nvim

docs: refine "zpack might be for you" section

fix: use vim.pack.get() as source of truth for ZClean

docs: tweak example config comment spacing for clarity

feat: warn about semver-like version on vim.pack.add error

docs(readme): add new logo and acknowledgement

docs: reorganize Usage section and add Plugin Spec examples

fix: ZDelete! includes zpack.nvim in deletion list

feat: ZDelete force deletes active plugins

docs: add Snacks.nvim dashboard workaround for lazy.nvim dependency

doc: consistent "batteries included" section header image

docs: clarify config and opts relationship in examples

fix: check buffer validity before re-triggering FileType events

feat: auto-expand dir field paths with vim.fn.expand()

refactor: move pack_spec creation from import to merge phase