feat(plugins): replace scooter find‑replace with grug‑far and add Python interpreter resolution

lua/plugins/grug-far.lua

@@ -0,0 +1,22 @@
+--- grug-far.nvim: buffer-based find & replace, backing the <C-r> binds in
+--- plugins/astrocore.lua. Replaces the scooter TUI (nvim-external-tui, gone).
+--- Buffer-local actions hang off <localleader> (`,`): `,r` replace,
+--- `,s` sync all lines, `,l` sync line, `,q` quickfix, `,c` close, `g?` help.
+--- @module plugins.grug-far
+
+return {
+  "MagicDuck/grug-far.nvim",
+  cmd = { "GrugFar", "GrugFarWithin" },
+  opts = {
+    -- ripgrep only: no ast-grep binary on this machine, so keep the
+    -- astgrep engines out of the Swap Engine (`,e`) cycle
+    enabledEngines = { "ripgrep" },
+
+    -- right-hand split, matching where scooter used to open
+    windowCreationCommand = "botright vsplit",
+
+    -- linewise selection (V) limits search/replace to that range,
+    -- charwise selection (v) prefills the search input instead
+    visualSelectionUsage = "auto-detect",
+  },
+}