fix: remove unused fs-extra dep, dedupe zod, preserve empty-string env var coercion

Empty-string env vars now reach the schema coercion layer (matching v3
behavior where '' produced false for booleans and 0 for numbers).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: B4nan

packages/core/package.json

@@ -59,7 +59,6 @@
         "@sapphire/async-queue": "^1.5.5",
         "@vladfrangu/async_event_emitter": "^2.4.6",
         "csv-stringify": "^6.5.2",
-        "fs-extra": "^11.3.0",
         "json5": "^2.2.3",
         "minimatch": "^10.0.1",
         "ow": "^2.0.0",

packages/core/src/configuration.ts

@@ -264,14 +264,16 @@ export class Configuration {
     }
 
     /**
-     * Reads the first non-empty env var value for a field definition.
+     * Reads the first defined env var value for a field definition.
+     * Empty strings are passed through — schema coercion handles them
+     * (e.g. `coerceBoolean` treats `''` as `false`).
      */
     private static readEnvVar(fieldDef: ConfigField): string | undefined {
         if (!fieldDef.envVar) return undefined;
         const envVars = Array.isArray(fieldDef.envVar) ? fieldDef.envVar : [fieldDef.envVar];
         for (const envVar of envVars) {
             const value = process.env[envVar];
-            if (value != null && value !== '') return value;
+            if (value != null) return value;
         }
         return undefined;
     }

packages/core/test/core/configuration.test.ts

@@ -106,6 +106,22 @@ describe('Configuration', () => {
             expect(new Configuration().headless).toBe(true);
         });
 
+        it('treats empty-string boolean env var as false', () => {
+            setEnv('CRAWLEE_HEADLESS', '');
+            expect(new Configuration().headless).toBe(false);
+
+            setEnv('CRAWLEE_PURGE_ON_START', '');
+            expect(new Configuration().purgeOnStart).toBe(false);
+        });
+
+        it('coerces empty-string number env var to 0', () => {
+            setEnv('CRAWLEE_PERSIST_STATE_INTERVAL_MILLIS', '');
+            expect(new Configuration().persistStateIntervalMillis).toBe(0);
+
+            setEnv('CRAWLEE_MEMORY_MBYTES', '');
+            expect(new Configuration().memoryMbytes).toBe(0);
+        });
+
         it('coerces number env vars', () => {
             setEnv('CRAWLEE_PERSIST_STATE_INTERVAL_MILLIS', '30000');
             expect(new Configuration().persistStateIntervalMillis).toBe(30_000);

yarn.lock

@@ -961,7 +961,6 @@ __metadata:
     "@sapphire/async-queue": "npm:^1.5.5"
     "@vladfrangu/async_event_emitter": "npm:^2.4.6"
     csv-stringify: "npm:^6.5.2"
-    fs-extra: "npm:^11.3.0"
     json5: "npm:^2.2.3"
     minimatch: "npm:^10.0.1"
     ow: "npm:^2.0.0"
@@ -15922,16 +15921,9 @@ __metadata:
   languageName: node
   linkType: hard
 
-"zod@npm:^3.24.0 || ^4.0.0":
+"zod@npm:^3.24.0 || ^4.0.0, zod@npm:^3.25 || ^4.0, zod@npm:^4.3.5":
   version: 4.3.6
   resolution: "zod@npm:4.3.6"
   checksum: 10c0/860d25a81ab41d33aa25f8d0d07b091a04acb426e605f396227a796e9e800c44723ed96d0f53a512b57be3d1520f45bf69c0cb3b378a232a00787a2609625307
   languageName: node
   linkType: hard
-
-"zod@npm:^3.25 || ^4.0, zod@npm:^4.3.5":
-  version: 4.3.5
-  resolution: "zod@npm:4.3.5"
-  checksum: 10c0/5a2db7e59177a3d7e202543f5136cb87b97b047b77c8a3d824098d3fa8b80d3aa40a0a5f296965c3b82dfdccdd05dbbfacce91347f16a39c675680fd7b1ab109
-  languageName: node
-  linkType: hard