feat(memory): dedicated Memory screen (moved out of System tab) (#835)

* feat(memory): dedicated Memory screen — providers, builtin files & reset (moved from System tab)

* feat(memory): move self-improvement & learning activity section from System tab to Memory screen

* fix(memory): remove top padding, single-line reset buttons, providers spacing

* fix(memory): tighten provider card padding

* fix(memory): distinct AutoStories icon for Memory tab

* chore: ignore local debug apk

* feat(ui): fresh icon set for drawer screens

* feat(ui): custom Neurology icon for Memory tab

* fix(ui): theme-driven fill for NeurologyIcon (checkColorLiterals)

The custom Neurology vector used SolidColor(Color.Black), tripping the
hardcoded-color guard (issue #622). The fill only contributes alpha —
Icon()'s tint replaces the RGB at draw time, mirroring Material's own
icon set — so the literal belongs in theme/ like every other hardcoded
color: new IconDefaultFill token, scoped there by the guard's design.

---------

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

app/src/test/java/com/m57/hermescontrol/ui/system/SystemViewModelTest.kt

@@ -48,11 +48,4 @@ class SystemViewModelTest {
         viewModel.closeUpdateConfirm()
         assertFalse(viewModel.uiState.value.updateConfirmOpen)
     }
-
-    @Test
-    fun `initial uiState has null learningGraph`() {
-        val viewModel = SystemViewModel()
-
-        org.junit.Assert.assertNull(viewModel.uiState.value.learningGraph)
-    }
 }