Creating a high-level mermaid block diagram for your project involves structuring the various components into a clear representation. Here's how the components of your project can be represented in a mermaid block diagram format, highlighting key components and their manufacturer part numbers (MPNs) whenever provided. Note that for simplicity, connections between every pin may not be detailed, and power nets or grounds may be represented generally to focus on functional blocks and interactions.

Note: This diagram simplifies connections and focuses on the main components. The Arduino Nano acts as the central controller, interacting with sensors, controlling relays, LEDs, and interfacing with communication modules like the DS1307 (Real-Time Clock) and AT24C256 (EEPROM). Every resistor, diode, and transistor is represented in groups for clarity, without detailing each connection to the microcontroller. The "Diodes" block includes all diodes used in the project with their respective MPNs where available. Similarly, the "Transistors" block collectively represents NPN transistors used. PowerNet elements and grounds are generally represented to focus on the functional connections and interactions.

This arrangement provides a high-level overview, useful for understanding the project components and their interactions at a glance.

Creating a high-level Mermaid block diagram of your project involves organizing the main components and their relationships in a simplified manner. Let's focus on key components and their connections based on your project's description. Given the broad scope and complexity of the project with numerous components and nets, I'll highlight essential elements and their connections for clarity.

Please note, Mermaid diagrams in this context are textual representations used for simplicity. To visualize this Mermaid diagram, you'd use a tool or platform that supports Mermaid syntax.

This diagram highlights the core functional blocks and their interconnections, including control paths from the Arduino Nano to other components like the buzzer module, proximity sensor interface, relays, and the LED. It also shows the power management components connecting to various power jumper headers (JP), and the interaction between the AT24C256 EEPROM and the DS1307 Real-Time Clock via I2C. The relays and their control paths are also highlighted, indicating how they are driven by the Arduino and potentially manual override interfaces.

The chosen components for depiction in the block diagram are based on their role in control, sensing, and power management, considering their importance in the overall project functionality. This abstract representation might not include every detail of the project or the specific data lines used for connection but attempts to provide a simplified overview of the system's architecture.