feat: graft pyxis onto upstream microReticulum 0.4.1

Repins microReticulum + microLXMF onto the upstream-0.4.1 graft and adapts
pyxis to the new src/microReticulum/ layout and 0.4.x APIs. The far-diverged
0.3.0 fork's Resource/Transport/Identity work is subsumed by upstream's
reimplementation; only the still-needed fixes ride on the pinned branches
(PKCS7/HMAC/X25519 crypto -- proven byte-identical to python RNS 1.3.1 --
Packet link-proof callback, Identity short-sig guard, and the bz2 layer +
decompress-on-receive in Resource::assemble()).

Consumer-side changes:
- platformio.ini: pin microReticulum @2f21fee (pyxis-fixes-on-0.4.1) and
  microLXMF @33760d0 (chore/microreticulum-0.4.1-layout); bump microStore
  ceea8f5 -> c5fb69d (0.4.x requires the new BasicFileStore::init API);
  -std=gnu++11 -> gnu++17 (upstream requires C++17).
- Namespace all microReticulum includes (angle + quote) to <microReticulum/...>
  for the relocated layout; shim-local Utilities/Stream.h|Print.h preserved.
- Interface::send_outgoing now returns bool: update TCP/BLE/SX1262/Auto
  overrides with correct success/failure returns.
- SDArchiveFileSystem::init(bool reformatOnFail=true) to match new microStore.
- Static Transport::get_path_table() -> path_table(); instance getter unchanged.
- Remove duplicate shim Cryptography/BZ2 (microReticulum provides it now; keep
  lib/libbz2 as the ESP32 bzlib provider).
- patch_littlefs_paths.py: normalize microStore's LittleFS adapter paths to a
  leading "/" -- ESP32 Arduino LittleFS rejects "./"-prefixed paths, which
  silently broke the path store (no peer paths learned, all messaging blocked).

Validated on T-Deck Plus: builds (RAM 27.5% / Flash 77.7%), boots stable
(no WDT/panic), and a full on-device LXMF e2e (DIRECT + OPPORTUNISTIC +
bz2-compressed-Resource receive) passes 5/5.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UWZuYkHBRqNb6BZHV8sTG5

src/TCPClientInterface.cpp

@@ -1,8 +1,8 @@
 #include "TCPClientInterface.h"
 #include "HDLC.h"
 
-#include <Transport.h>
-#include <Log.h>
+#include <microReticulum/Transport.h>
+#include <microReticulum/Log.h>
 
 #include <memory>
 
@@ -440,12 +440,12 @@ void TCPClientInterface::extract_and_process_frames() {
     }
 }
 
-/*virtual*/ void TCPClientInterface::send_outgoing(const Bytes& data) {
+/*virtual*/ bool TCPClientInterface::send_outgoing(const Bytes& data) {
     DEBUG(toString() + ".send_outgoing: data: " + std::to_string(data.size()) + " bytes");
 
     if (!_online) {
         DEBUG("TCPClientInterface: Not connected, cannot send");
-        return;
+        return false;
     }
 
     try {
@@ -484,7 +484,7 @@ void TCPClientInterface::extract_and_process_frames() {
             ERROR("TCPClientInterface: Write incomplete, " + std::to_string(written) +
                   " of " + std::to_string(framed.size()) + " bytes");
             handle_disconnect();
-            return;
+            return false;
         }
         _client.flush();
 #else
@@ -492,21 +492,23 @@ void TCPClientInterface::extract_and_process_frames() {
         if (written < 0) {
             ERROR("TCPClientInterface: send error " + std::to_string(errno));
             handle_disconnect();
-            return;
+            return false;
         }
         if (static_cast<size_t>(written) != framed.size()) {
             ERROR("TCPClientInterface: Write incomplete, " + std::to_string(written) +
                   " of " + std::to_string(framed.size()) + " bytes");
             handle_disconnect();
-            return;
+            return false;
         }
 #endif
 
         // Perform post-send housekeeping
         InterfaceImpl::handle_outgoing(data);
+        return true;
 
     } catch (std::exception& e) {
         ERROR("TCPClientInterface: Exception during send: " + std::string(e.what()));
         handle_disconnect();
     }
+    return false;
 }