Updated docs and updated API to fetch signal descriptors in all modes

API and Protocol docs have been updated (GPT 5.6)

The API methods for fetching a sepcific signal descriptor and fetching
all signal descriptors now work in offline mode, the core_tui.py example
has been updated to fit the new tri mode architecture and loading
recording offload -> processing and then processing -> playback engine
all works

src/dynalab_core/dlpak.py

@@ -2,6 +2,7 @@
 # Copyright (C) 2026 Association Exergie <association.exergie@gmail.com>
 # SPDX-License-Identifier: GPL-3.0-or-later
 
+from copy import copy
 from datetime import datetime, timezone
 import logging
 from pathlib import Path
@@ -58,6 +59,9 @@ class DLPak:
             timestamp=timestamp, signals=manifest_signals, comments=""
         )
 
+    def get_all_signal_descriptors(self) -> list[SignalDescriptor]:
+        return copy([signal.to_pure() for signal in self._manifest.signals])
+
     def read(self, file: str | Path) -> Self:
         input_path = Path(file)