optimization: Scope access is now a Kotlin interface, compiler uses direct slot access also for closures

notes/ai_state.md

@@ -7,12 +7,16 @@ Current focus
 - Enforce compile-time name/member resolution only; no runtime scope lookup or fallback.
 - Bytecode uses memberId-based ops (CALL_MEMBER_SLOT/GET_MEMBER_SLOT/SET_MEMBER_SLOT).
 - Runtime lookup opcodes (CALL_VIRTUAL/GET_FIELD/SET_FIELD) and fallback callsites are removed.
+- Migrate bytecode to frame-first locals with lazy scope reflection; avoid eager scope slot plans in compiled functions.
+- Use FrameSlotRef for captures and only materialize Scope for Kotlin interop; use frame.ip -> pos mapping for diagnostics.
 
 Key recent changes
 - Removed method callsite PICs and fallback opcodes; bytecode now relies on compile-time member ids only.
 - Operator dispatch emits memberId calls when known; falls back to Obj opcodes for allowed built-ins without name lookup.
 - Object members are allowed on unknown types; other members still require a statically known receiver type.
-- Renamed BytecodeFallbackException to BytecodeCompileException.
+- Added frame.ip -> pos mapping; call-site ops restore pos after args to keep stack traces accurate.
+- Loop var overrides now take precedence in slot resolution to keep loop locals in frame slots.
+- LocalSlotRef now falls back to name lookup when slot plans are missing (closure safety).
 
 Known failing tests
 - None (jvmTest passing).
@@ -20,14 +24,12 @@ Known failing tests
 Files touched recently
 - notes/type_system_spec.md (spec updated)
 - AGENTS.md (type inference reminders)
-- lynglib/src/commonMain/kotlin/net/sergeych/lyng/VarDeclStatement.kt
 - lynglib/src/commonMain/kotlin/net/sergeych/lyng/Compiler.kt
 - lynglib/src/commonMain/kotlin/net/sergeych/lyng/bytecode/BytecodeCompiler.kt
-- lynglib/src/commonMain/kotlin/net/sergeych/lyng/obj/ObjIterable.kt
-- various bytecode runtime/disassembler files (memberId ops)
+- lynglib/src/commonMain/kotlin/net/sergeych/lyng/obj/ObjRef.kt
 
 Last test run
-- ./gradlew :lynglib:jvmTest --tests ScriptTest.testForInIterableUnknownTypeDisasm
+- ./gradlew :lynglib:jvmTest
 
 Spec decisions (notes/type_system_spec.md)
 - Nullability: Kotlin-style, T non-null, T? nullable, !! asserts non-null.