feat: Add status bar option "Full w/ Progress Bar" (#438)

## Summary

* **What is the goal of this PR?** This PR introduces a new "Status Bar"
mode that displays a visual progress bar at the bottom of the screen,
providing readers with a graphical indication of their position within
the book.
* **What changes are included?** 

* **Settings**: Updated SettingsActivity to expand the "Status Bar"
configuration with a new option: Full w/ Progress Bar.
* **EPUB Reader**: Modified EpubReaderActivity to calculate the global
book progress and render a progress bar at the bottom of the viewable
area when the new setting is active.
* **TXT Reader**: Modified TxtReaderActivity to implement similar
progress bar rendering logic based on the current page and total page
count.

## Additional Context

* The progress bar is rendered with a height of 4 pixels at the very
bottom of the screen (adjusted for margins).
* The feature reuses the existing renderStatusBar logic but
conditionally draws the bar instead of (or in addition to) other
elements depending on the specific implementation details in each
reader.
  * Renamed existing 'Full' mode to 'Full w/ Percentage'
  * Added new 'Full w/ Progress Bar' option

<img
src="https://github.com/user-attachments/assets/08c0dd49-c64c-4d4d-9fbb-f576c02d05d9"
width="500">


---

### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? _**NO**_

src/activities/settings/SettingsActivity.cpp

@@ -16,7 +16,8 @@ const SettingInfo displaySettings[displaySettingsCount] = {
     // Should match with SLEEP_SCREEN_MODE
     SettingInfo::Enum("Sleep Screen", &CrossPointSettings::sleepScreen, {"Dark", "Light", "Custom", "Cover", "None"}),
     SettingInfo::Enum("Sleep Screen Cover Mode", &CrossPointSettings::sleepScreenCoverMode, {"Fit", "Crop"}),
-    SettingInfo::Enum("Status Bar", &CrossPointSettings::statusBar, {"None", "No Progress", "Full"}),
+    SettingInfo::Enum("Status Bar", &CrossPointSettings::statusBar,
+                      {"None", "No Progress", "Full w/ Percentage", "Full w/ Progress Bar", "Progress Bar"}),
     SettingInfo::Enum("Hide Battery %", &CrossPointSettings::hideBatteryPercentage, {"Never", "In Reader", "Always"}),
     SettingInfo::Enum("Refresh Frequency", &CrossPointSettings::refreshFrequency,
                       {"1 page", "5 pages", "10 pages", "15 pages", "30 pages"})};