bytecode: extend call args and cache call sites

notes/bytecode_callsite_cache.md

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+# Bytecode method call-site cache
+
+Changes
+- Added per-thread bytecode method call-site caches via BytecodeCallSiteCache expect/actuals.
+- Bytecode VM now reuses per-function call-site maps to preserve method PIC hits across repeated bytecode executions.
+- Removed unused methodCallSites property from BytecodeFunction.
+
+Why
+- Fixes JVM PIC invalidation test by allowing method PIC hits when bytecode bodies are invoked repeatedly (e.g., loop bodies compiled to bytecode statements).
+- Avoids cross-thread mutable map sharing on native by using thread-local storage.
+
+Tests
+- ./gradlew :lynglib:jvmTest
+- ./gradlew :lynglib:allTests -x :lynglib:jvmTest
+
+Benchmark
+- ./gradlew :lynglib:jvmTest --tests NestedRangeBenchmarkTest -Dbenchmarks=true
+  - nested-happy elapsed=1266 ms