Replaces AstroNvim v5 with from-scratch Neovim 0.12 config using vim.lsp.config()/vim.lsp.enable() natively, lazy.nvim, blink.cmp, and smart-splits tmux integration. tmux: new C-Space prefix, hjkl pane nav, resize key table, tpm plugins. kitty: add allow_remote_control for smart-splits.