Align level parity docs and fetch/status validation

- Add LevelsCompare.md with setup and validation comparisons against Gazler/githug.
- Document that LevelsCompare.md must be updated when level behavior changes.
- Track FETCH_HEAD count in RepoState so the Fetch level can match upstream validation.
- Mirror upstream Status setup with staged files plus untracked database.yml.
- Keep Fetch from being solved by pull despite native Git FETCH_HEAD behavior.
- Bump app version and build debug APK.

app/src/main/java/solutions/tretter/githugandroid/levels/FetchLevel.kt

@@ -15,7 +15,15 @@ internal fun fetchLevel(): Level = level(
     description = "Looks like a new branch was pushed into our remote repository. Get the changes without merging them with the local repository",
     hints = listOf("Look up the 'git fetch' command"),
     commandSuggestions = listOf("git fetch origin"),
-    setup = { RepoState(initialized = true, branches = mapOf("master" to 1), remotes = mapOf("origin" to "remote")) },
+    setup = {
+        RepoState(
+            initialized = true,
+            branches = mapOf("master" to 1),
+            remotes = mapOf("origin" to "remote"),
+            fetchedBranches = setOf("origin/master"),
+            fetchHeadCount = 1,
+        )
+    },
     nativeSetup = {
         resetFiles()
         write("master_file")
@@ -33,9 +41,9 @@ internal fun fetchLevel(): Level = level(
         true
     },
     validator = repoPredicate { repo ->
-        "fetch" in repo.maintenanceActions &&
-            "origin/new_branch" in repo.fetchedBranches &&
-            repo.headBranch == "master"
+        repo.branches.size == 1 &&
+            repo.fetchHeadCount == 2 &&
+            "pull" !in repo.maintenanceActions
     },
     testCases = listOf(
         levelTestCase("fetch origin", "git fetch origin"),