Add CallGraphFromTo query for all supported languages

[data-douser]

Scope

Add CallGraphFromTo transitive call reachability query for all 8 CallGraph-supporting languages (cpp, csharp, go, java, javascript, python, ruby, swift).

Files

• server/ql/*/tools/src/CallGraphFromTo/CallGraphFromTo.ql — query implementation (8 files)
• server/ql/*/tools/src/CallGraphFromTo/CallGraphFromTo.md — documentation (8 files)
• server/ql/*/tools/test/CallGraphFromTo/ — tests + expected output (24 files)
• server/ql/go/tools/src/PrintAST/PrintAST.ql — fix for Go PrintAST
• server/ql/java/tools/src/PrintCFG/PrintCFG.ql — fix for Java PrintCFG
• server/src/lib/cli-tool-registry.ts — external predicate handling for CallGraphFromTo

Independence

✅ The .ql queries, .md docs, and test files are fully independent. The external predicate wiring in cli-tool-registry.ts also touches server code but is a small, focused change.

Notes

• Uses calls* transitive closure with both sourceFunction and targetFunction external predicates
• All 8 languages compile and pass unit tests
• External predicate handling also fixed to work with direct query paths (not just queryName)

Parent: #163