feat: Connect to last wifi by default (#752)

## Summary

* **What is the goal of this PR?** 

Use last connected network as default

* **What changes are included?**

- Refactor how an action type of Settings are handled
- Add a new System Settings option → Network
- Add the ability to forget a network in the Network Selection Screen
- Add the ability to Refresh network list
- Save the last connected network SSID
- Use the last connection whenever network is needed (OPDS, Koreader
sync, update etc)

## Additional Context

* Add any other information that might be helpful for the reviewer
(e.g., performance implications, potential risks,
  specific areas to focus on).


![IMG_6504](https://github.com/user-attachments/assets/e48fb013-b5c3-45c0-b284-e183e6fd5a68)

![IMG_6503](https://github.com/user-attachments/assets/78c4b6b6-4e7b-4656-b356-19d65ff6aa12)




https://github.com/user-attachments/assets/95bf34a8-44ce-4279-8cd8-f78524ce745b





---

### AI Usage

Did you use AI tools to help write this code? _** PARTIALLY: I wrote
most of it but I also used Gemini as assist.

---------

Co-authored-by: Eliz Kilic <elizk@google.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

src/activities/settings/SettingsActivity.h

@@ -14,11 +14,22 @@ class CrossPointSettings;
 
 enum class SettingType { TOGGLE, ENUM, ACTION, VALUE, STRING };
 
+enum class SettingAction {
+  None,
+  RemapFrontButtons,
+  KOReaderSync,
+  OPDSBrowser,
+  Network,
+  ClearCache,
+  CheckForUpdates,
+};
+
 struct SettingInfo {
   const char* name;
   SettingType type;
   uint8_t CrossPointSettings::* valuePtr = nullptr;
   std::vector<std::string> enumValues;
+  SettingAction action = SettingAction::None;
 
   struct ValueRange {
     uint8_t min;
@@ -63,10 +74,11 @@ struct SettingInfo {
     return s;
   }
 
-  static SettingInfo Action(const char* name) {
+  static SettingInfo Action(const char* name, SettingAction action) {
     SettingInfo s;
     s.name = name;
     s.type = SettingType::ACTION;
+    s.action = action;
     return s;
   }
 
@@ -156,4 +168,4 @@ class SettingsActivity final : public ActivityWithSubactivity {
   void onEnter() override;
   void onExit() override;
   void loop() override;
-};
+};