🚀 Major LLVM breakthrough by ChatGPT5\!

PHI type coercion and core-first routing fixes:
- Auto type conversion for PHI nodes (i64↔i8*↔i1↔f64)
- Fixed ArrayBox.get misrouting to Map path
- Core-first strategy for Array/Map creation
- Added comprehensive debug logging ([PHI], [ARR], [MAP])

Results:
✅ Array smoke test: 'Result: 3'
✅ Map smoke test: 'Map: v=42, size=1'

After 34+ minutes of battling Rust lifetime errors,
ChatGPT5 achieved a major breakthrough\!

Key insight: The bug wasn't in PHI/SSA logic but in
Box type routing - ArrayBox.get was incorrectly caught
by Map fallback due to missing annotations.

We're SO CLOSE to Nyash self-hosting paradise\! 🌟
Once this stabilizes, everything can be written in
simple, beautiful Nyash code instead of Rust complexity.

src/backend/llvm/compiler/codegen/instructions/boxcall/invoke.rs

@@ -177,8 +177,19 @@ fn store_invoke_return<'ctx>(
                 }
             }
             crate::mir::MirType::String => {
-                // keep as i64 handle
-                vmap.insert(dst, rv);
+                // Normalize to i8* for String to align with PHI/type inference
+                // Plugins return i64 handle; convert handle -> i8* here.
+                let h = if let BVE::IntValue(iv) = rv {
+                    iv
+                } else {
+                    return Err("invoke ret expected i64 for String".to_string());
+                };
+                let pty = codegen.context.ptr_type(inkwell::AddressSpace::from(0));
+                let ptr = codegen
+                    .builder
+                    .build_int_to_ptr(h, pty, "ret_string_handle_to_ptr")
+                    .map_err(|e| e.to_string())?;
+                vmap.insert(dst, ptr.into());
             }
             crate::mir::MirType::Box(_)
             | crate::mir::MirType::Array(_)