#175: Kotlin bench scopes cut at every type, trace selection walks once per root, and an unbalanced annotation costs only its line

[devmaxxx]

Summary

• Closes JVM bench selection residuals carried over from #133 #175.
• Kotlin call-graph owners. di_call_graph used to cut Kotlin files at each class line, and only after a short list of modifiers. That missed object, interface, and enum, value and private classes, and it charged every file-level function after a class to that class. Kotlin scopes now come from blanked text (kotlin_scopes). Each named type owns its lines up to the point where its brackets close. After a nested type ends, the lines that follow belong to the enclosing type again. A companion object belongs to its class, which is how the store reads it. A type named only in a comment or a string opens no scope. Other languages keep the existing cut through DiReader.cls.
• Names that two scopes share. The graph now also returns shared: every name that more than one scope declares, nested types included. select_jvm_cases drops a trace whose end or via hop is one of those names and counts it under trace_name_two_scopes_share. The reason: the graph merges both classes' calls under one name, and member_chain only checks the file that declared kept.
• One BFS per root. shortest_paths(graph, src) gives every destination the exact path that shortest_path(graph, src, dst) returns, and trace selection now runs one walk per root instead of one per pair.
• Unbalanced annotation brackets. In Java, an annotation argument list that never closed used to blank the rest of the file. In Kotlin, its open ( stopped every later declaration from being read. blank_java and blank_kotlin now cut such a list back to the end of its own line, so declarations and declaration_end both recover. A closing bracket of the wrong kind no longer closes the list. Balanced annotations and Kotlin labels (return@forEach, this@A) are unchanged.

Test plan

• New tests failed before the fix and pass after it:
  • KotlinCallScopes (3 tests)
  • ShortestPaths: every pair across 42 graphs (a diamond, a chain longer than the hop limit, and 40 seeded random graphs) against shortest_path
  • UnbalancedAnnotations (4 tests)
  • SharedNames in test_select_jvm_cases.py (2 tests)
• python3 -m unittest discover -s bench/compare: 242 tests OK
• python3 -m unittest discover -s bench/probe: 148 tests OK
• python3 -m unittest discover -s bench/history: 56 tests OK
• The one-walk selection matches the per-pair version: with only that change applied, select() from origin/main and from this branch gave byte-identical blast.jsonl, truth.json and summaries on ten fixtures (SHOP, the split-method fixture, and eight seeded 24-class Java/Kotlin corpora with up to 173 trace candidates).
• Pinned beauty-crm fixture (126 .kt files): the truth for all 10 graded trace cases in bench/blast.jsonl and bench/corpora/beauty-crm-mobile/blast.jsonl is unchanged. The annotation bound changes the blanked text of no file. The Kotlin edges that moved are corrections: library calls (List.*, Map.*, JsonObject.*) that the old cut charged to the wrong class, plus private and value classes that the old cut missed.