feat: improve LSP lifecycle, terminal widget, and code folding support

- LSP:
  - Add shutdown and exit request/notification handling
  - Send initialized notification after initialize response
  - Gracefully close clients with delayed shutdown via GLib timeout
  - Fix LSP WS server ↔ Godot LSP communication flow

- Terminal (VteWidget):
  - Switch to async spawn with full environment inheritance
  - Add PROMPT_COMMAND OSC7 support for cwd tracking
  - Improve UX: scrollback, no audible bell, auto scroll
  - Implement clipboard shortcuts, selection copy, middle-click paste
  - Track cwd changes and update UI label
  - Add proper signal wiring and cleanup on destroy

- Code folding:
  - Add fold support for JS, HTML, CSS, JSON, C, C++, Go
  - Reset fold state safely when AST or filetype is unavailable

- UI (Plugins dialog):
  - Improve dialog behavior (non-modal, centered, transient)
  - Add focus-out auto-hide and Ctrl+Shift+P shortcut

- Misc:
  - Add type hints in VTE widget
  - Update TODOs (remove completed items, add LSP comm fix)
  - Add terminal plugin scaffolding

plugins/code/ui/terminals/terminals_view.py

@@ -0,0 +1,142 @@
+# Python imports
+
+# Lib imports
+import gi
+gi.require_version('Gtk', '3.0')
+gi.require_version('Gdk', '3.0')
+
+from gi.repository import Gtk
+from gi.repository import GLib
+from gi.repository import Gdk
+from gi.repository import Pango
+
+# Application imports
+from .vte_widget import VteWidget
+
+
+
+class TerminalsView(Gtk.Notebook):
+    def __init__(self):
+        super(TerminalsView, self).__init__()
+
+        self.code_view = None
+
+        self._setup_styling()
+        self._setup_signals()
+        self._load_widgets()
+
+        self.show_all()
+        self.hide()
+
+
+    def _setup_styling(self):
+        ctx = self.get_style_context()
+        ctx.add_class("terminals-view")
+
+        self.set_scrollable(True)
+
+    def _setup_signals(self):
+        self.connect("show", self._handle_show)
+        self.connect("hide", self._handle_hide)
+        self.connect("destroy", self._handle_destroy)
+
+    def _load_widgets(self):
+        hbox           = Gtk.Box()
+        self.add_bttn  = Gtk.Button(label = "✛")
+        self.hide_bttn = Gtk.Button(label = "－")
+        self.add_bttn.connect("clicked", self._create_terminal)
+        self.hide_bttn.connect("clicked", self._hide_view)
+
+        hbox.add(self.add_bttn)
+        hbox.add(self.hide_bttn)
+        self.set_action_widget(hbox, Gtk.PackType.END)
+
+        self.create_terminal()
+        hbox.show_all()
+
+    def _generate_terminal_parts(self):
+        label      = Gtk.Label(label = "...")
+        vte_widget = VteWidget()
+
+        vte_widget.hide_view       = self.hide
+        vte_widget.create_terminal = self.create_terminal
+        vte_widget.close_terminal  = self.close_terminal
+        vte_widget.prev_terminal   = self.prev_terminal
+        vte_widget.next_terminal   = self.next_terminal
+
+        label.set_text( vte_widget.get_home_path() )
+        label.set_tooltip_text( vte_widget.get_home_path() )
+        label.set_ellipsize(Pango.EllipsizeMode.START)
+        label.set_single_line_mode(True)
+        label.set_max_width_chars(32)
+        label.set_size_request(240, -1)
+
+        vte_widget.bind_label(label)
+
+        return label, vte_widget
+
+    def _handle_show(self, widget):
+        i    = widget.get_current_page()
+        term = widget.get_nth_page(i)
+
+        GLib.idle_add(term.grab_focus)
+
+    def _handle_hide(self, widget):
+        if not self.code_view: return
+        GLib.idle_add(self.code_view.grab_focus)
+
+    def _hide_view(self, widget):
+        self.hide()
+
+    def _handle_destroy(self, widget):
+        widget.disconnect_by_func(widget._handle_show)
+        widget.disconnect_by_func(widget._handle_hide)
+        widget.disconnect_by_func(widget._handle_destroy)
+        self.add_bttn.disconnect_by_func(self._create_terminal)
+        self.hide_bttn.disconnect_by_func(self._hide_view)
+
+    def _create_terminal(self, widget):
+        self.create_terminal()
+
+    def set_code_view(self, widget):
+        self.code_view = widget
+
+    def create_terminal(self):
+        label, vte_widget = self._generate_terminal_parts()
+        index = self.append_page(vte_widget, label)
+        self.set_tab_detachable(vte_widget, True)
+        self.set_tab_reorderable(vte_widget, True)
+
+        self.set_current_page(index)
+        GLib.idle_add(vte_widget.grab_focus)
+
+        self.show_all()
+
+    def close_terminal(self):
+        size = self.get_n_pages()
+        if size == 1: return
+
+        i     = self.get_current_page() 
+        widget = self.get_nth_page(i)
+        self.remove_page(i)
+        widget.destroy()
+
+    def prev_terminal(self):
+        i    = self.get_current_page() - 1
+        size = self.get_n_pages()
+
+        if i < 0:
+            self.set_current_page(size - 1)
+            return
+
+        self.prev_page()
+
+    def next_terminal(self):
+        i    = self.get_current_page() + 1
+        size = self.get_n_pages()
+
+        if i == size:
+            self.set_current_page(0)
+            return
+
+        self.next_page()