feat(arm64): add ARM64/aarch64 QML support with pinned PyQt6 dependencies

- Pin qml_gui extras in setup.py to PyQt6>=6.7.0,<6.8.0, PyQt6-Qt6>=6.7.0,<6.8.0
  and PyQt6-sip==13.10.2 for compatibility on both x86_64 and aarch64 architectures
- Add ARM64/aarch64 QML GUI installation instructions in README.md with the exact
  pinned package versions required for correct operation on Apple Silicon and
  Linux ARM64 systems

README.md

@@ -53,9 +53,7 @@ If you want to run Pallectrum from source, you'll need Python 3.10 or higher.
 
 #### Windows
 
-**Prerequisites:**
-
-- Python 3.10+ installed from [python.org](https://www.python.org/downloads/)
+**Prerequisites:**  Python 3.10+ installed from [python.org](https://www.python.org/downloads/)
 
 **Setup with Virtual Environment:**
 
@@ -88,16 +86,20 @@ python run_electrum gui -g qml
 
 #### Linux (Ubuntu/Debian)
 
-**Install Prerequisites:**
+##### Install Prerequisites
 
 ```bash
 # System packages
 sudo apt update
-sudo apt install -y python3-venv python3-pip build-essential python3-dev
-sudo apt install -y libffi-dev libssl-dev libsecp256k1-dev
+sudo apt install -y \
+  python3-venv python3-pip python3-dev build-essential \
+  libffi-dev libssl-dev libsecp256k1-dev \
+  libpulse0
 ```
 
-**Setup with Virtual Environment:**
+---
+
+##### Standard Installation (x86_64)
 
 ```bash
 # Clone repository
@@ -108,23 +110,73 @@ cd pallectrum
 python3 -m venv env
 source env/bin/activate
 
-# Upgrade pip and install dependencies
+# Upgrade pip
 python3 -m pip install --upgrade pip
-pip install -e ".[gui,crypto]"
+
+# Install project with GUI + crypto extras
+pip install -e "[gui,crypto]"
 
 # Run with Qt GUI
 python run_electrum
 ```
 
-##### Optional: QML GUI on Linux (simulates Android interface)
+---
+
+##### ARM64 (aarch64)
+
+> PyQt6 ≥ 6.9 wheels are not available for ARM64 on PyPI. Use pinned versions.
 
 ```bash
-pip install ".[qml_gui]"
+# Clone repository (if not already done)
+git clone https://github.com/palladium-coin/pallectrum.git
+cd pallectrum
+
+# Create and activate virtual environment
+python3 -m venv env
+source env/bin/activate
+
+# Upgrade pip
+python3 -m pip install --upgrade pip
+
+# Base requirements
+pip install -r contrib/requirements/requirements.txt
+pip install "cryptography>=2.6"
+
+# Install ARM64-compatible PyQt6 versions
+pip install --only-binary PyQt6,PyQt6-Qt6,PyQt6-sip \
+  "PyQt6>=6.7.0,<6.8.0" \
+  "PyQt6-Qt6>=6.7.0,<6.8.0" \
+  "PyQt6-sip==13.10.2"
+
+# Install project (development mode)
+pip install -e .
+
+# Run
+python run_electrum
+```
+
+---
+
+##### Optional: QML GUI (Android-like interface)
+
+###### x86_64
+
+```bash
+pip install "[qml_gui]"
 python run_electrum gui -g qml
 ```
 
-For detailed installation instructions, including dependencies and platform-specific notes, see the [original Electrum documentation](README-ELECTRUM.md#getting-started).
+###### ARM64
 
+```bash
+python run_electrum gui -g qml
+```
+
+---
+
+For detailed installation instructions, including dependencies and platform-specific notes, see the original Electrum documentation:
+
+[README-ELECTRUM.md#getting-started](README-ELECTRUM.md#getting-started)
 
 ## User Guide
 

setup.py

@@ -45,7 +45,11 @@ extras_require = {
     'gui': ['pyqt6'],
     'crypto': ['cryptography>=2.6'],
     'tests': ['pycryptodomex>=3.7', 'cryptography>=2.6', 'pyaes>=0.1a1'],
-    'qml_gui': ['pyqt6<6.6', 'pyqt6-qt6<6.6']
+    'qml_gui': [
+        'pyqt6>=6.7.0,<6.8.0',
+        'pyqt6-qt6>=6.7.0,<6.8.0',
+        'pyqt6-sip==13.10.2',
+    ],
 }
 # 'full' extra that tries to grab everything an enduser would need (except for libsecp256k1...)
 extras_require['full'] = [pkg for sublist in