s3vectors: put, get and delete vector bucket policies (#12201)

* util: do not bind outbound dials to a loopback -ip.bind

`weed server -ip.bind=127.0.0.1` keeps every listener local, but the
same address became the source of outbound connections, so the filer
dialled its remote mount from 127.0.0.1 and failed with "connect:
invalid argument". A loopback source cannot reach off the host; leave
the source to the OS, as for a wildcard bind.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* s3vectors: put, get and delete vector bucket policies

The AWS S3 Vectors policy operations had no handlers; the policy document
is stored on the shared table bucket, so the handlers delegate to the
catalog's PutTableBucketPolicy, GetTableBucketPolicy and
DeleteTableBucketPolicy and keep its guard.

* s3vectors: treat ICEBERG buckets as absent in policy handlers

GetVectorBucketPolicy/PutVectorBucketPolicy/DeleteVectorBucketPolicy
delegated straight to the table bucket, so a bucket created for ICEBERG
tables — invisible to every other vectors operation — could still have
its policy read and written through the vectors API. Gate all three on
lanceBucket, the same format check DeleteVectorBucket and CreateIndex
already apply.

* test/vectors: cover vector bucket policy put/get/delete

Round-trips a policy document through the new ops and asserts a get on
the deleted policy surfaces NotFoundException, so the boto3 conformance
run exercises the added handlers end to end.

* s3vectors: validate the bucket ARN and policy document

Bucket-level operations now reject an index ARN and an ARN minted for
another service, and PutVectorBucketPolicy refuses a document carrying
s3vectors actions — the evaluator only honors s3tables actions, so such a
rule would be a dead grant.

* s3vectors: validate the bucket ARN on the remaining bucket-level operations

* s3vectors: cover bucket ARN and policy document validation

TestBucketARNs pins the accepted forms and the index/foreign-service
rejections; TestValidatePolicyDocument covers a valid document, a
malformed one, and the dead s3vectors action namespace.

* s3vectors test: use an enforceable action in the bucket policy test

The catalog refuses s3vectors actions in a stored policy, so the put call
rejected the document before the get and delete assertions ran.

---------

Co-authored-by: Ólafur Bjarki Bogason <olafur@genkiinstruments.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

test/vectors/s3vectors_test.py

@@ -4,8 +4,11 @@ Run via `make test` — a mini cluster, an s3 gateway serving the vectors API on
 weed-vector are up by then.
 """
 
+import json
+
 import boto3
 import pytest
+from botocore.exceptions import ClientError
 
 ENDPOINT = "http://127.0.0.1:8334"
 BUCKET = "vectors-bucket"
@@ -79,3 +82,31 @@ def test_vector_lifecycle(vectors):
 
     vectors.delete_index(vectorBucketName=BUCKET, indexName=INDEX)
     vectors.delete_vector_bucket(vectorBucketName=BUCKET)
+
+
+def test_vector_bucket_policy(vectors):
+    vectors.create_vector_bucket(vectorBucketName=BUCKET)
+    try:
+        policy = json.dumps(
+            {
+                "Version": "2012-10-17",
+                "Statement": [
+                    {
+                        "Effect": "Allow",
+                        "Principal": {"AWS": "*"},
+                        "Action": "s3tables:*",
+                        "Resource": "*",
+                    }
+                ],
+            }
+        )
+        vectors.put_vector_bucket_policy(vectorBucketName=BUCKET, policy=policy)
+        got = vectors.get_vector_bucket_policy(vectorBucketName=BUCKET)["policy"]
+        assert json.loads(got) == json.loads(policy)
+
+        vectors.delete_vector_bucket_policy(vectorBucketName=BUCKET)
+        with pytest.raises(ClientError) as exc:
+            vectors.get_vector_bucket_policy(vectorBucketName=BUCKET)
+        assert exc.value.response["Error"]["Code"] == "NotFoundException"
+    finally:
+        vectors.delete_vector_bucket(vectorBucketName=BUCKET)