fix: harden store writes, strict schemas, null cfg

test/unit/config/store.test.ts

@@ -78,6 +78,13 @@ describe('store', () => {
         writeStore(path, [connection])
         expect(readFileSync(path, 'utf8')).toContain('\n    "name": "lab"')
     })
+
+    it('cleans up the tmp file when rename fails', () => {
+        mkdirSync(path, { recursive: true })
+        expect(() => writeStore(path, [connection])).toThrow()
+        const leftovers = readdirSync(join(dir, 'nested')).filter((f) => f.includes('.tmp'))
+        expect(leftovers).toEqual([])
+    })
 })
 
 describe('defaultStorePath', () => {