fix(protect): use canonical JSONPath format for root-level array indices

- Handle paths starting with '[' to produce $[0] instead of $.[0]
- Update test expectation for root-level array index
- Add edge case tests: large indices, deeply nested paths, nested arrays

Author: tobyhede

packages/protect/__tests__/jsonb-helpers.test.ts

@@ -51,7 +51,19 @@ describe('toJsonPath', () => {
   })
 
   it('handles array index at root level', () => {
-    expect(toJsonPath('[0].name')).toBe('$.[0].name')
+    expect(toJsonPath('[0].name')).toBe('$[0].name')
+  })
+
+  it('handles large array index', () => {
+    expect(toJsonPath('items[999].value')).toBe('$.items[999].value')
+  })
+
+  it('handles deeply nested path after array index', () => {
+    expect(toJsonPath('data[0].user.profile.settings')).toBe('$.data[0].user.profile.settings')
+  })
+
+  it('handles root array with nested array', () => {
+    expect(toJsonPath('[0].items[1].name')).toBe('$[0].items[1].name')
   })
 })
 

packages/protect/src/helpers/jsonb.ts

@@ -20,6 +20,7 @@ export function toJsonPath(path: string): string {
   if (path.startsWith('$.')) return path
   if (path.startsWith('$')) return `$.${path.slice(1)}`
   if (path.startsWith('.')) return `$${path}`
+  if (path.startsWith('[')) return `$${path}`
   return `$.${path}`
 }