Improve upstream parity for level fixtures

- Add native per-level fixtures for complex histories, tags, branch graphs, rebases, resets, restores, stashes, and local remotes.
- Strengthen repository inspection so branch commit counts, remote-tracking branches, and detached tag checkouts reflect real Git state.
- Align Fetch, Pull, Push Branch, Branch At, and Rebase validators/tests with upstream-style repository state.
- Keep the prompt callout and native filesystem tab-completion fixes from the previous batch.

app/src/main/java/solutions/tretter/githugandroid/Terminal.kt

@@ -37,9 +37,12 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.focus.FocusRequester
 import androidx.compose.ui.focus.focusRequester
 import androidx.compose.ui.focus.onFocusChanged
+import androidx.compose.ui.geometry.Rect
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.Path
 import androidx.compose.ui.graphics.SolidColor
+import androidx.compose.ui.layout.boundsInRoot
+import androidx.compose.ui.layout.onGloballyPositioned
 import androidx.compose.ui.platform.LocalConfiguration
 import androidx.compose.ui.platform.LocalFocusManager
 import androidx.compose.ui.platform.LocalSoftwareKeyboardController
@@ -69,6 +72,7 @@ fun TerminalPane(
     onCursorRight: () -> Unit,
     onHistoryUp: () -> Unit,
     onHistoryDown: () -> Unit,
+    onPromptBoundsChanged: (Rect) -> Unit = {},
 ) {
     val configuration = LocalConfiguration.current
     val focusRequester = remember { FocusRequester() }
@@ -161,6 +165,9 @@ fun TerminalPane(
                 modifier = Modifier
                     .fillMaxWidth()
                     .widthIn(min = terminalMinWidth)
+                    .onGloballyPositioned { coordinates ->
+                        onPromptBoundsChanged(coordinates.boundsInRoot())
+                    }
                     .background(PanelPrimary, RoundedCornerShape(8.dp))
                     .padding(horizontal = 8.dp, vertical = 3.dp),
                 verticalAlignment = Alignment.CenterVertically,