S3: Enforce bucket policy (#7471)

* evaluate policies during authorization

* cache bucket policy

* refactor

* matching with regex special characters

* Case Sensitivity, pattern cache, Dead Code Removal

* Fixed Typo, Restored []string Case, Added Cache Size Limit

* hook up with policy engine

* remove old implementation

* action mapping

* validate

* if not specified, fall through to IAM checks

* fmt

* Fail-close on policy evaluation errors

* Explicit `Allow` bypasses IAM checks

* fix error message

* arn:seaweed => arn:aws

* remove legacy support

* fix tests

* Clean up bucket policy after this test

* fix for tests

* address comments

* security fixes

* fix tests

* temp comment out

weed/iam/policy/policy_engine.go

@@ -95,7 +95,7 @@ type EvaluationContext struct {
 	// Action being requested (e.g., "s3:GetObject")
 	Action string `json:"action"`
 
-	// Resource being accessed (e.g., "arn:seaweed:s3:::bucket/key")
+	// Resource being accessed (e.g., "arn:aws:s3:::bucket/key")
 	Resource string `json:"resource"`
 
 	// RequestContext contains additional request information