Refactor: Consolidate navigation items into ScreenRegistry (#310)

* Refactor: Consolidate navigation items into ScreenRegistry

* fix(#310): remove unused imports, fix ktlint import ordering

* feat(#289): add ScreenRegistry for centralized screen configuration

* fix(#310): fix ktlint when-condition blank lines in Navigation.kt

* fix(#289): derive availableNavItems from ScreenRegistry

* fix(#310): use addEntryProvider instead of reified entry for dynamic screen registration

* fix(#310): remove double top padding from kanban, channels, achievements screens

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Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/ui/channels/ChannelsScreen.kt

@@ -93,7 +93,7 @@ fun ChannelsScreen(
 
             else -> {
                 LazyColumn(
-                    modifier = Modifier.fillMaxSize().padding(paddingValues),
+                    modifier = Modifier.fillMaxSize(),
                     contentPadding = listContentPadding,
                     verticalArrangement = listItemSpacing,
                 ) {