feat: Ghost Shell v2 — AGS v3 statusbar + violet-chaton v2 palette

- AGS v3.1.0 (Astal/GTK3) Ghost Shell avec ghost mode (heartbeat + hover reveal)
- Modules : clock, battery, volume (interactif), network, MPRIS, CPU/RAM, systray
- Brain Power panel (Super + B) — lecture live focus/todos/session
- tetardtek_ prompt avec curseur clignotant
- Palette violet-chaton v2 documentée (Mitsuri Kanroji gradient magenta → green)
- Autostart COSMIC via .desktop
- Archive AGS v1 conservée pour référence

ags-v3/widget/panels/BrainPower.tsx

@@ -0,0 +1,104 @@
+import app from "ags/gtk3/app"
+import { Astal, Gtk, Gdk } from "ags/gtk3"
+import { createPoll } from "ags/time"
+import { getBrainState } from "../../lib/brain"
+
+function BrainContent() {
+  const state = createPoll("", 10000, () => JSON.stringify(getBrainState()))
+
+  const focus = state((s: string) => {
+    try { return JSON.parse(s).focus } catch { return "..." }
+  })
+
+  const todosLabel = state((s: string) => {
+    try {
+      const t = JSON.parse(s).todos
+      return `${t.open} ouverts / ${t.done} faits`
+    } catch { return "..." }
+  })
+
+  const todosList = state((s: string) => {
+    try {
+      const t = JSON.parse(s).todos.top3
+      return t.map((item: string) => `  ⬜ ${item}`).join("\n") || "  rien"
+    } catch { return "..." }
+  })
+
+  const session = state((s: string) => {
+    try {
+      const sess = JSON.parse(s).session
+      return sess || "aucune"
+    } catch { return "..." }
+  })
+
+  return (
+    <box orientation={Gtk.Orientation.VERTICAL} class="brain-content">
+      <box class="brain-section">
+        <label class="brain-section-title" label="  FOCUS" xalign={0} />
+      </box>
+      <label class="brain-focus" label={focus} xalign={0} wrap />
+
+      <box class="brain-divider" />
+
+      <box class="brain-section">
+        <label class="brain-section-title" label="  SESSION" xalign={0} />
+      </box>
+      <label class="brain-session" label={session} xalign={0} />
+
+      <box class="brain-divider" />
+
+      <box class="brain-section">
+        <label class="brain-section-title" label="󰄲  TODOS" xalign={0} />
+        <label class="brain-todos-count" label={todosLabel} xalign={1} hexpand />
+      </box>
+      <label class="brain-todos-list" label={todosList} xalign={0} />
+
+      <box class="brain-divider" />
+
+      <box class="brain-section">
+        <label class="brain-section-title" label="  TERMINAL" xalign={0} />
+      </box>
+      <label class="brain-terminal-placeholder" label="  bientôt — agent brain-hud" xalign={0} />
+    </box>
+  )
+}
+
+export default function BrainPower(gdkmonitor: Gdk.Monitor) {
+  const { TOP, LEFT, BOTTOM } = Astal.WindowAnchor
+
+  return (
+    <window
+      class="BrainPower"
+      name="brain-power"
+      visible={false}
+      gdkmonitor={gdkmonitor}
+      exclusivity={Astal.Exclusivity.NONE}
+      anchor={TOP | LEFT | BOTTOM}
+      application={app}
+      layer={Astal.Layer.OVERLAY}
+    >
+      <eventbox
+        onHoverLost={() => {
+          const win = app.get_window("brain-power")
+          if (win) win.visible = false
+        }}
+      >
+        <box orientation={Gtk.Orientation.VERTICAL} class="brain-panel">
+          <box class="brain-header">
+            <label class="brain-title" label="  BRAIN POWER" hexpand xalign={0} />
+            <button
+              class="brain-close"
+              onClicked={() => {
+                const win = app.get_window("brain-power")
+                if (win) win.visible = false
+              }}
+            >
+              <label label="✕" />
+            </button>
+          </box>
+          <BrainContent />
+        </box>
+      </eventbox>
+    </window>
+  )
+}