refactor: sequential scan, screens for details, new sidebar layout

- Scan sequential with asyncio.to_thread for proper Textual integration
- Use push_screen/pop_screen for package/CVE lists (no more mount/remove)
- Sidebar now shows 'APT X CVE X' with right-aligned indicators
- Loader uses black circles (⚫) for pending tasks
- Removed unused package_table.py and cve_table.py

full_updater/ui/detail_screens.py

@@ -0,0 +1,80 @@
+from textual.screen import Screen
+from textual.widgets import DataTable, Button, Static
+from textual.containers import Vertical, Horizontal
+
+try:
+    import pyperclip
+    PYPERCLIP_OK = True
+except Exception:
+    PYPERCLIP_OK = False
+
+
+class PackageListScreen(Screen):
+    BINDINGS = [("b", "back", "Retour")]
+
+    def __init__(self, packages: list[dict]):
+        super().__init__()
+        self.packages = packages
+
+    def compose(self):
+        with Vertical():
+            with Horizontal(id="pkg-toolbar"):
+                yield Button("⬅ Retour", id="pkg-back", variant="default")
+            table = DataTable(id="pkg-table")
+            table.add_columns("Nom", "Version actuelle", "Nouvelle version", "Taille")
+            for pkg in self.packages:
+                table.add_row(pkg.get("name", "?"), pkg.get("current", "?"), pkg.get("new", "?"), pkg.get("size", "-"))
+            yield table
+
+    def on_button_pressed(self, event: Button.Pressed):
+        if event.button.id == "pkg-back":
+            self.app.pop_screen()
+
+    def action_back(self):
+        self.app.pop_screen()
+
+
+class CVEListScreen(Screen):
+    BINDINGS = [("b", "back", "Retour")]
+
+    def __init__(self, cves: list[dict]):
+        super().__init__()
+        self.cves = cves
+        self.urls = {}
+
+    def compose(self):
+        with Vertical():
+            with Horizontal(id="cve-toolbar"):
+                yield Button("⬅ Retour", id="cve-back", variant="default")
+            table = DataTable(id="cve-table")
+            table.add_columns("CVE-ID", "Paquet", "Lien")
+            table.cursor_type = "row"
+            for i, cve in enumerate(self.cves):
+                cve_id = cve.get("id", "?")
+                pkg = cve.get("package", "?")
+                url = cve.get("url", "")
+                self.urls[i] = url
+                table.add_row(cve_id, pkg, url)
+            yield table
+
+    def on_data_table_row_selected(self, event: DataTable.RowSelected):
+        row_key = event.row_key
+        row_index = list(self.query_one("#cve-table").rows.keys()).index(row_key)
+        url = self.urls.get(row_index, "")
+        if not url:
+            return
+        if PYPERCLIP_OK:
+            try:
+                pyperclip.copy(url)
+                self.notify(f"Lien copié : {url}", severity="information")
+                return
+            except Exception:
+                pass
+        self.notify(f"Lien (copie manuelle) : {url}", severity="warning")
+
+    def on_button_pressed(self, event: Button.Pressed):
+        if event.button.id == "cve-back":
+            self.app.pop_screen()
+
+    def action_back(self):
+        self.app.pop_screen()