Install & Neovim Bootstrap Revamp

Ongoing work on fully revamping my dot-files install.sh and Neovim stack.

Dotfiles bootstrap is now modular and declarative.
install.sh handles symlinks, backups, plugin sync, and full lazy.nvim bootstrap automatically.
Neovim config is framework-free, built from scratch with isolated plugin control.
Full lazy-loading using lazy.nvim, with sniper-level loading precision.
LSP, CMP, Treesitter, and nvim-tree properly initialized using config blocks.
Keymaps handled via which-key with full namespace documentation.

Work in progress. Updates and refinements will continue over the next days.