Resolve #1843 - avoid running dexie in double instances.

1. Export ony one require-based module and a MJS wrapper for it. Skip dual export.
2. Detect double instances and let 2nd instance return same instance as was already imported.

import-wrapper-prod.mjs

@@ -1,7 +1,12 @@
 // Making the module version consumable via require - to prohibit
 // multiple occurrancies of the same module in the same app
 // (dual package hazard, https://nodejs.org/api/packages.html#dual-package-hazard)
-import Dexie from "./dist/dexie.min.js";
+import _Dexie from "./dist/dexie.min.js";
+const DexieSymbol = Symbol.for("Dexie");
+const Dexie = globalThis[DexieSymbol] || (globalThis[DexieSymbol] = _Dexie);
+if (_Dexie.semVer !== Dexie.semVer) {
+    throw new Error(`Two different versions of Dexie loaded in the same app: ${_Dexie.semVer} and ${Dexie.semVer}`);
+}
 const { liveQuery, mergeRanges, rangesOverlap, RangeSet, cmp } = Dexie;
 export { liveQuery, mergeRanges, rangesOverlap, RangeSet, cmp, Dexie };
 export default Dexie;

import-wrapper.mjs

@@ -1,7 +1,12 @@
 // Making the module version consumable via require - to prohibit
 // multiple occurrancies of the same module in the same app
 // (dual package hazard, https://nodejs.org/api/packages.html#dual-package-hazard)
-import Dexie from "./dist/dexie.js";
+import _Dexie from "./dist/dexie.js";
+const DexieSymbol = Symbol.for("Dexie");
+const Dexie = globalThis[DexieSymbol] || (globalThis[DexieSymbol] = _Dexie);
+if (_Dexie.semVer !== Dexie.semVer) {
+    throw new Error(`Two different versions of Dexie loaded in the same app: ${_Dexie.semVer} and ${Dexie.semVer}`);
+}
 const { liveQuery, mergeRanges, rangesOverlap, RangeSet, cmp } = Dexie;
 export { liveQuery, mergeRanges, rangesOverlap, RangeSet, cmp, Dexie };
 export default Dexie;

package.json

@@ -8,22 +8,19 @@
   "exports": {
     ".": {
       "production": {
-        "browser": "./dist/modern/dexie.min.mjs",
-        "module": "./dist/modern/dexie.min.mjs",
+        "module": "./import-wrapper-prod.mjs",
         "import": "./import-wrapper-prod.mjs",
         "require": "./dist/dexie.min.js",
         "default": "./dist/dexie.min.js"
       },
       "development": {
-        "browser": "./dist/modern/dexie.mjs",
-        "module": "./dist/modern/dexie.mjs",
+        "module": "./import-wrapper.mjs",
         "import": "./import-wrapper.mjs",
         "require": "./dist/dexie.js",
         "default": "./dist/dexie.js"
       },
       "default": {
-        "browser": "./dist/modern/dexie.mjs",
-        "module": "./dist/modern/dexie.mjs",
+        "module": "./import-wrapper.mjs",
         "import": "./import-wrapper.mjs",
         "require": "./dist/dexie.js",
         "default": "./dist/dexie.js"