feat(neovim): add OSC 52 clipboard support for SSH sessions

Lets "+y/"+p sync with the system clipboard over SSH (Termius -> VPS/homelab)
without relying on a local clipboard provider.

home/emmatherock/neovim.nix

@@ -16,6 +16,24 @@
 
     globals.mapleader = " ";
 
+    # --- System clipboard over OSC 52, so "+y / "+p work over SSH
+    #     (Termius -> VPS/homelab) without a local clipboard provider.
+    #     Requires Neovim 0.10+ for vim.ui.clipboard.osc52; confirmed
+    #     present (Neovim 0.12.5 on the pinned nixpkgs as of 2026-09).
+    extraConfigLua = ''
+      vim.g.clipboard = {
+        name = "OSC 52",
+        copy = {
+          ["+"] = require("vim.ui.clipboard.osc52").copy("+"),
+          ["*"] = require("vim.ui.clipboard.osc52").copy("*"),
+        },
+        paste = {
+          ["+"] = require("vim.ui.clipboard.osc52").paste("+"),
+          ["*"] = require("vim.ui.clipboard.osc52").paste("*"),
+        },
+      }
+    '';
+
     opts = {
       number = true;
       relativenumber = true;