refactor(hyprland): replace kitty-herdr with tern and adjust keybindings

- Replaced `kitty-herdr` with `tern` as the default scratchpad terminal
  across configs, scripts, and docs.
- Remapped window resize controls to `SUPER + CTRL + HJKL` and monitor
  navigation to `ALT` modifiers.
- Removed the `scrolloverview` plugin configuration and cleaned up
  obsolete menu bindings.

dot_config/hypr/hyprland.lua

@@ -50,9 +50,10 @@ o.window([[^tldraw-offline$]], { workspace = "5", fullscreen = true })
 -- them; "silent" leaves the reveal to the script. Under the master layout the
 -- first window to appear takes the master slot; the rest stack beside it.
 --
--- SUPER + A / SUPER + CTRL + S: kitty/herdr; SUPER + SHIFT + A: Claude
--- Desktop. Each alone on its own workspace, Studio Display.
-o.window([[^kitty-herdr$]], { workspace = "special:scratchpad silent" })
+-- SUPER + A / SUPER + CTRL + S: Tern; SUPER + SHIFT + A: Claude Desktop.
+-- Each alone on its own workspace, Studio Display. Tern has no per-window
+-- class flag, so every Tern window lands on the scratchpad.
+o.window([[^so\.stencil\.tern$]], { workspace = "special:scratchpad silent" })
 o.window([[^com\.anthropic\.Claude$]], { workspace = "special:claude silent" })
 -- SUPER + CTRL + ALT + E / M: Fastmail and Beeper, each alone on the
 -- focused monitor.