建立ToolDbProcessPort合约层

结论：已新增ToolDbProcessPort合约、OPFS tool DB flat-file/transcript store和Node/WASM gates，baseline保持28/28/131/0且promotion继续锁定。

wasm-port/runtime/opfs/tool-db-store.js

@@ -0,0 +1,78 @@
+import { loadTextFile, saveTextFile } from "./file-service.js";
+import { toolDbFilePath, toolDbTranscriptPath } from "./path-model.js";
+
+function stableTextHash(text) {
+  let hash = 0x811c9dc5;
+  for (let index = 0; index < text.length; index += 1) {
+    hash ^= text.charCodeAt(index);
+    hash = Math.imul(hash, 0x01000193) >>> 0;
+  }
+  return hash.toString(16).padStart(8, "0");
+}
+
+function displayOpfsPath(path) {
+  return path.startsWith("linuxcnc/") ? path.slice("linuxcnc".length) : `/${path}`;
+}
+
+export function createToolDbStorePaths(machineId, {
+  dbFilename = "db_nonran_file",
+  runId = "run-1",
+  transcriptFilename = "transcript.json",
+} = {}) {
+  return {
+    dbFile: toolDbFilePath(machineId, dbFilename),
+    transcript: toolDbTranscriptPath(machineId, runId, transcriptFilename),
+  };
+}
+
+export async function saveToolDbFile(machineId, text, options = {}) {
+  const path = options.path ?? toolDbFilePath(machineId, options.filename);
+  await saveTextFile(path, text, options.storage);
+  return {
+    opfsPath: path,
+    displayPath: displayOpfsPath(path),
+    dbFileHash: stableTextHash(text),
+    savedText: text,
+  };
+}
+
+export async function loadToolDbFile(machineId, options = {}) {
+  const path = options.path ?? toolDbFilePath(machineId, options.filename);
+  const text = await loadTextFile(path, options.storage);
+  return {
+    opfsPath: path,
+    displayPath: displayOpfsPath(path),
+    dbFileHash: stableTextHash(text),
+    text,
+  };
+}
+
+export async function saveToolDbTranscript(machineId, runId, transcript, options = {}) {
+  if (!Array.isArray(transcript)) {
+    throw new Error("transcript must be an array.");
+  }
+  const path = options.path ?? toolDbTranscriptPath(machineId, runId, options.filename);
+  const text = JSON.stringify({
+    schema: "linuxcnc.toolDbProcessTranscript.v1",
+    transcript,
+  }, null, 2);
+  await saveTextFile(path, text, options.storage);
+  return {
+    opfsPath: path,
+    displayPath: displayOpfsPath(path),
+    transcriptHash: stableTextHash(text),
+    text,
+  };
+}
+
+export async function loadToolDbTranscript(machineId, runId, options = {}) {
+  const path = options.path ?? toolDbTranscriptPath(machineId, runId, options.filename);
+  const text = await loadTextFile(path, options.storage);
+  const payload = JSON.parse(text);
+  return {
+    opfsPath: path,
+    displayPath: displayOpfsPath(path),
+    transcriptHash: stableTextHash(text),
+    payload,
+  };
+}