Start the Go rewrite: jsjson, awg-ctrl port, differential bench

- internal/jsjson: JSON.stringify-compatible encoder and order-preserving decoder,
  tested against fixtures produced by Node itself
- internal/ctrl: awg-ctrl in Go (params, vpn:// keys, users, peers, sync, 3.1
  upgrade, CAKE shaping, metrics, monitor job, Express-compatible HTTP layer)
- internal/iauth, internal/logx: internal Ed25519 tokens and logging
- tools/diffbench: Docker bench with stubbed awg/ip/tc/nft that runs one scenario
  against the TS and Go implementations for comparison

tools/golden/jsjson.mjs

@@ -0,0 +1,23 @@
+// Эталон для internal/jsjson: вывод JSON.stringify самого Node на каверзных значениях.
+// Запуск: node tools/golden/jsjson.mjs > testdata/golden/jsjson.json
+const strings = [
+  "", "plain", "кириллица", "emoji 😀", "<r 2><b 0x85>", "a&b<c>d", "slash/и\\обратный",
+  "quote\"q", "line\nbreak", "tab\tcr\r", "\b\f", "\u0000\u0001\u001f\u007f", "

",
+  "I2 = ", "  spaces  ", "ü", "日本語",
+];
+const numbers = [0, -0, 1, -1, 1376, 47619, 0.1, 0.5, 1.5, 2.5, 100.25, 1e21, 1e20, 123456789012345680000,
+  1e-7, 1e-6, 0.000001234, 1.7976931348623157e308, 5e-324, 3.14159, -273.15, 2 ** 53, 2 ** 53 + 2, 0.1 + 0.2, 250.5,
+  NaN, Infinity, -Infinity];
+const objects = [
+  { a: 1, b: "x", c: [1, 2, { d: null }], e: true, f: false },
+  { rekey: false, endpoints: ["1.2.3.4:443"], servers: [{ id: 0, name: "VPN & <co>
", awg: { Jc: "6", I1: "<r 2>" } }] },
+  { empty: {}, arr: [], nested: { x: [] } },
+  [],
+  {},
+];
+const out = {
+  strings: strings.map(s => ({ in: s, out: JSON.stringify(s) })),
+  numbers: numbers.map(n => ({ in: Number.isFinite(n) ? n : String(n), out: JSON.stringify(n), str: String(n) })),
+  objects: objects.map(o => ({ in: o, compact: JSON.stringify(o), indent2: JSON.stringify(o, null, 2) })),
+};
+process.stdout.write(JSON.stringify(out, null, 1));