[Feature Request] Option to Configure Network Power Management

### Have you tried?

- [Searching through existing/closed issues](https://github.com/AdnanHodzic/auto-cpufreq/issues) to see if your bug has already been already submitted?
Ans: Yes, no prior issue found
- Have you tried [configuring auto-cpufreq](https://github.com/AdnanHodzic/auto-cpufreq/#configuring-auto-cpufreq)?
Ans: Yes
- Have you tried suggestions in [troubleshooting section](https://github.com/AdnanHodzic/auto-cpufreq#troubleshooting)?
Ans: Yes
---
Currently, auto-cpufreq automatically disables the network connection after a period of inactivity. While this behavior can save power, it can be disruptive for users who need consistent network connectivity. Most laptops come with a dedicated network button/shortcut for users who prefer manual control, and as mentioned on [Discord](https://discord.com/channels/1158239366251020361/1158252850841919498/1303086261736706078), Adnan has encouraged submitting feature request for it too.

- Default behavior is fine. However, there is a need to give users options to customize it.

### Current Behavior
- Network connection is automatically disabled after a period of inactivity
- Forces manual reconnection by clicking on the network again
- Happens even when actively using the system (e.g., watching cached videos)

### Requested Feature
Add configuration options in the auto-cpufreq config file to:
- Disable automatic network power management completely
- Configure the inactivity timeout period
- Potentially add different settings for battery vs AC power

### Few Use Cases
1. Watching streamed content with buffered/cached data
2. Waiting for background downloads or updates
3. Applications that require constant connectivity (like chat apps)

### Why This Matters
The current behavior can be disruptive for users who need consistent network connectivity, especially in scenarios where the network appears inactive but is actually needed for maintaining connection state.

### Suggested Implementation Example
Add new configuration options in the config file:
```ini
[network]
# Enable/disable network power management
enable_power_saving = true

# Time in seconds before network is considered inactive
inactivity_timeout = 300

# Different settings for charger/battery
# If not specified, will use enable_power_saving value
charger_power_saving = false
battery_power_saving = true
```