nvim,tmux,kitty: full config overhaul (AstroNvim → native 0.12)

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.

dot_config/nvim/lua/plugins/obsidian.lua

@@ -1,40 +1,2 @@
----@type LazySpec
-return {
-  "obsidian-nvim/obsidian.nvim",
-  version = "*", -- recommended, use latest release instead of latest commit
-  lazy = true,
-  ft = "markdown",
-  -- Replace the above line with this if you only want to load obsidian.nvim for markdown files in your vault:
-  -- event = {
-  --   -- If you want to use the home shortcut '~' here you need to call 'vim.fn.expand'.
-  --   -- E.g. "BufReadPre " .. vim.fn.expand "~" .. "/my-vault/*.md"
-  --   -- refer to `:h file-pattern` for more examples
-  --   "BufReadPre path/to/my-vault/*.md",
-  --   "BufNewFile path/to/my-vault/*.md",
-  -- },
-  dependencies = {
-    -- Required.
-    "nvim-lua/plenary.nvim",
-
-    -- see above for full list of optional dependencies ☝️
-  },
-  ---@module 'obsidian'
-  ---@type obsidian.config.ClientOpts
-  opts = {
-    workspaces = {
-      {
-        name = "uni",
-        path = "~/Documents/uni",
-      },
-    },
-    -- Optional, completion of wiki links, local markdown links, and tags using nvim-cmp.
-    completion = {
-      -- Enables completion using nvim_cmp
-      nvim_cmp = false,
-      -- Enables completion using blink.cmp
-      blink = true,
-      -- Trigger completion at 2 chars.
-      min_chars = 2,
-    },
-  },
-}
+-- Removed: not part of the from-scratch config
+return {}