Fix 9 issues: kiro package data, betweenness perf, wiki step, opencode plugin, cache root, PHP missing edges, Windows stability, cross-file calls

- #352: add skill-kiro.md to pyproject.toml package-data
- #341: guard edge_betweenness at >5000 nodes; use approximate k=100 for suggest_questions on large graphs
- #354/#229: add Step 6b in skill.md to call to_wiki() when --wiki given (before Step 9 cleanup)
- #356: call _install_opencode_plugin() from install --platform opencode path
- #350: add cache_root param to extract() so subdirectory runs keep cache at ./graphify-out/cache/
- #230: PHP class_constant_access_expression emits references_constant edges
- #232: PHP scoped_call_expression (static method calls) emits calls edges
- #287: os.replace fallback for Windows WinError 5; graphify update exits 1 on failure; templates use graphify update . instead of python3 -c
- #348: cross-file call resolution for all languages via raw_calls + global label map pass in extract()

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/test_claude_md.py

@@ -22,7 +22,7 @@ def test_install_contains_expected_rules(tmp_path):
     content = (tmp_path / "CLAUDE.md").read_text()
     assert "GRAPH_REPORT.md" in content
     assert "wiki/index.md" in content
-    assert "_rebuild_code" in content
+    assert "graphify update" in content
 
 
 def test_install_appends_to_existing_claude_md(tmp_path):