feat: Wave 3 — plugin loader + Flet GUI (parity with Rust fork)

Plugin loader (mirrors Rust #29):
- plugins_store.py walks %APPDATA%\com.priler.jarvis\plugins\<name>\
  for commands.yaml fragments and merges them into VA_CMD_LIST at
  startup. Same schema as the project root commands.yaml. Per-pack
  `disabled` flag file skips a pack without deletion. Built-in ids
  win conflicts so a malicious pack can't silently override
  open_browser. 9 unit tests (parity with the Rust tests).
- main.py: plugin merge runs after the root yaml load; logs the
  number of extra commands picked up.

Flet GUI (#27 — first parity with the Rust Tauri GUI):
- New gui/ package: __main__.py launches via `python -m gui` (or
  gui.bat). app.py routes between 7 pages (Главная / Команды /
  Макросы / Расписание / Память / Плагины / Настройки) via
  NavigationRail; dark theme matching the Tauri look.
- gui/services.py centralises every store-module call the pages
  share — single place to swap implementations later.
- One file per page in gui/pages/, all expose `build(page)` and use
  the same card layout idiom. Pages mirror the Tauri ones feature-
  for-feature: home (status + counters + launcher), commands
  (filterable list of all VA_CMD_LIST entries), macros (list +
  delete + recording banner), scheduler (list + remove), memory
  (add/forget/search), plugins (toggle/open folder), settings
  (profile + LLM hot-swap).
- requirements.txt: flet>=0.85 (optional; assistant runs without).
- 3 smoke tests verify imports + build callables; skip cleanly when
  Flet isn't installed.

README: documents both the GUI and the plugin layout in user-facing
terms. Tests: 42 → 54 (+9 plugins +3 GUI smoke).

gui/pages/memory.py

@@ -0,0 +1,74 @@
+"""Long-term memory page — list facts, add new ones, search, forget."""
+
+import flet as ft
+
+from gui import services as svc
+
+
+def build(page: ft.Page) -> ft.Control:
+    key_input = ft.TextField(label="Ключ", expand=True)
+    val_input = ft.TextField(label="Значение", expand=True)
+    search_input = ft.TextField(label="Поиск", expand=True)
+
+    list_view = ft.Column(spacing=6, expand=True, scroll=ft.ScrollMode.AUTO)
+
+    def render(query: str = ""):
+        list_view.controls.clear()
+        facts = svc.memory_search(query, limit=100) if query.strip() else svc.memory_all()
+        if not facts:
+            list_view.controls.append(ft.Text("Нет фактов. Скажи «Запомни что моя любимая еда — суши».",
+                                              color="#8aa0a8"))
+        for f in sorted(facts, key=lambda x: x.get("key", "")):
+            list_view.controls.append(_fact_row(f, on_forget=lambda k=f["key"]: do_forget(k)))
+        page.update()
+
+    def do_add(_):
+        k = key_input.value.strip()
+        v = val_input.value.strip()
+        if not k or not v:
+            return
+        svc.memory_remember(k, v)
+        key_input.value = ""
+        val_input.value = ""
+        render(search_input.value or "")
+
+    def do_forget(k: str):
+        svc.memory_forget(k)
+        render(search_input.value or "")
+
+    search_input.on_change = lambda e: render(e.control.value)
+    render()
+
+    return ft.Column(
+        [
+            ft.Text("Долговременная память", size=24, weight=ft.FontWeight.W_700),
+            ft.Text(
+                "Ключ-значение, которые Jarvis передаёт LLM как контекст пользователя.",
+                color="#8aa0a8", size=12,
+            ),
+            ft.Row([key_input, val_input, ft.FilledButton(text="Добавить", on_click=do_add)]),
+            search_input,
+            list_view,
+        ],
+        spacing=10,
+        expand=True,
+    )
+
+
+def _fact_row(f: dict, on_forget) -> ft.Control:
+    return ft.Container(
+        content=ft.Row([
+            ft.Column([
+                ft.Text(f.get("key", ""), weight=ft.FontWeight.W_600, size=13),
+                ft.Text(f.get("value", ""), size=12, color="#a8b8c0"),
+            ], spacing=2, expand=True),
+            ft.IconButton(
+                icon=ft.Icons.DELETE_FOREVER,
+                tooltip="Забыть",
+                on_click=lambda e: on_forget(),
+            ),
+        ]),
+        bgcolor="#15252b",
+        border_radius=8,
+        padding=ft.padding.symmetric(horizontal=12, vertical=8),
+    )