v1.5.2

Dual-slot PTY + status bar styling pass. The headline fix: KM8erm
(persistent embedded shell) can now coexist with kubectl exec /
kubectl edit — previously a hidden KM8erm shell blocked any new PTY,
forcing the user to exit it. Container drill gets a Space menu too, so
the v1.5.1 "Space = right-click menu" model now reaches the bottom of
the drill chain.

Added

• Dual-slot PTY architecture. Split the single m.ptyView into
  m.shellPty (KM8erm, persistent) and m.txPty (kubectl edit / exec,
  transient). They run independently — hide KM8erm in the background,
  then exec into a container without closing the shell session. Render
  layers tx on top of shell; input routing prefers tx; tick + exit
  messages carry Kind so the right slot cleans up.
• Container drill Space menu. Pressing Space while drilled into a
  pod's container list now opens a single-item menu (Shell) instead
  of doing nothing. S direct hotkey on the container row still works
  the same way — the menu just surfaces it so the v1.5.1 "Space =
  contextual menu" rule applies at every drill depth.

Changed

• Status bar text labels → Nerd Font icons. ctx: / cluster: /
  ns: replaced with \U+F0237 / \U+F1856 / \U+F51E — more compact,
  matches the KM8erm chip style. Hidden KM8erm chip color synced to
  the popup border (#F0AE49).
• PTY popup borders tri-color. With two PTYs able to coexist, each
  kind needs its own border so the active popup's provenance is
  unambiguous: KM8erm shell stays Catppuccin peach #F0AE49, kubectl exec switches to green #a6e3a1, kubectl edit keeps sky blue
  #74c7ec. Title (bold) shares each popup's border color.

Fixed

• Hidden KM8erm no longer blocks edit/exec. Old single-slot guard
  refused startShellExecMsg and startEditMsg whenever any PTY was
  alive — including a backgrounded KM8erm shell. Guards now check only
  the txPty slot, so the persistent shell stays out of the way.