pyvm: split op handlers into ops_core/ops_box/ops_ctrl; add ops_flow + intrinsic; delegate vm.py without behavior change

net-plugin: modularize constants (consts.rs) and sockets (sockets.rs); remove legacy commented socket code; fix unused imports
mir: move instruction unit tests to tests/mir_instruction_unit.rs (file lean-up); no semantic changes
runner/pyvm: ensure using pre-strip; misc docs updates

Build: cargo build ok; legacy cfg warnings remain as before

tools/test/smoke/mir/hints_jsonl_basic_smoke.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+root=$(cd "$(dirname "$0")"/../../../.. && pwd)
+bin="$root/target/release/nyash"
+
+if [ ! -x "$bin" ]; then
+  echo "nyash binary not found at $bin; build first (cargo build --release)" >&2
+  exit 1
+fi
+
+out_jsonl="$root/tmp/mir_hints_basic.jsonl"
+rm -f "$out_jsonl"
+
+# Emit scope + join hints into JSONL file (no stderr noise)
+export NYASH_PARSER_STAGE3=1
+export NYASH_MIR_HINTS="jsonl=$out_jsonl|scope|join"
+
+# Run two small samples that exercise both kinds (errors are tolerated, we only need hints emission)
+"$bin" --backend vm "$root/apps/tests/macro/exception/expr_postfix_direct.nyash" >/dev/null 2>&1 || true
+"$bin" --backend vm "$root/apps/tests/macro/if/assign_both_branches.nyash" >/dev/null 2>&1 || true
+
+test -s "$out_jsonl" || { echo "[FAIL] hints jsonl not created" >&2; exit 2; }
+
+# Basic presence checks (don’t overfit exact ids)
+rg -q '"kind":"ScopeEnter"' "$out_jsonl" || { echo "[FAIL] ScopeEnter not found in jsonl" >&2; exit 2; }
+rg -q '"kind":"JoinResult"' "$out_jsonl" || { echo "[FAIL] JoinResult not found in jsonl" >&2; exit 2; }
+
+echo "[OK] MIR hints JSONL basic smoke passed ($out_jsonl)"
+exit 0
+