feat: implement NIP-09 (deletions) and NIP-11 (relay info)

NIP-11 (Relay Information Document):
- Serves relay metadata at GET / with Accept: application/nostr+json
- Returns name, description, supported NIPs, limitations
- CORS headers for browser compatibility

NIP-09 (Event Deletion):
- Kind 5 events delete events referenced in 'e' tags
- Only authors can delete their own events
- Soft delete (marks deleted=1)
- Records deletion in deletions table
- Works across all protocols (gRPC, Connect, WebSocket)

Fixed deletions schema:
- deleted_event_id as PRIMARY KEY (not deletion_event_id)
- Allows one deletion event to delete multiple events

3 new tests, 44 total tests passing

Supported NIPs now: 1, 9, 11

1 files changed, 184 insertions, 0 deletions

diff --git a/internal/storage/deletions_test.go b/internal/storage/deletions_test.go
new file mode 100644
index 0000000..47e6547
--- /dev/null
+++ b/internal/storage/deletions_test.go
@@ -0,0 +1,184 @@
+package storage
+
+import (
+        "context"
+        "fmt"
+        "testing"
+        "time"
+
+        pb "northwest.io/nostr-grpc/api/nostr/v1"
+)
+
+func TestProcessDeletion(t *testing.T) {
+        store, err := New(":memory:")
+        if err != nil {
+                t.Fatalf("failed to create storage: %v", err)
+        }
+        defer store.Close()
+
+        ctx := context.Background()
+
+        event := &pb.Event{
+                Id:        "event123",
+                Pubkey:    "alice",
+                CreatedAt: time.Now().Unix(),
+                Kind:      1,
+                Tags:      []*pb.Tag{},
+                Content:   "to be deleted",
+                Sig:       "sig1",
+        }
+
+        err = store.StoreEvent(ctx, &EventData{
+                Event:         event,
+                CanonicalJSON: []byte(`[0,"alice",1234567890,1,[],"to be deleted"]`),
+        })
+        if err != nil {
+                t.Fatalf("failed to store event: %v", err)
+        }
+
+        retrieved, err := store.GetEvent(ctx, "event123")
+        if err != nil {
+                t.Fatalf("event should exist before deletion: %v", err)
+        }
+        if retrieved.Id != "event123" {
+                t.Errorf("expected event123, got %s", retrieved.Id)
+        }
+
+        deletionEvent := &pb.Event{
+                Id:        "deletion123",
+                Pubkey:    "alice",
+                CreatedAt: time.Now().Unix(),
+                Kind:      KindDeletion,
+                Tags: []*pb.Tag{
+                        {Values: []string{"e", "event123"}},
+                },
+                Content: "deleting my event",
+                Sig:     "sig2",
+        }
+
+        err = store.ProcessDeletion(ctx, deletionEvent)
+        if err != nil {
+                t.Fatalf("failed to process deletion: %v", err)
+        }
+
+        _, err = store.GetEvent(ctx, "event123")
+        if err != ErrEventNotFound {
+                t.Errorf("event should be deleted, got error: %v", err)
+        }
+}
+
+func TestProcessDeletionWrongAuthor(t *testing.T) {
+        store, err := New(":memory:")
+        if err != nil {
+                t.Fatalf("failed to create storage: %v", err)
+        }
+        defer store.Close()
+
+        ctx := context.Background()
+
+        event := &pb.Event{
+                Id:        "event456",
+                Pubkey:    "alice",
+                CreatedAt: time.Now().Unix(),
+                Kind:      1,
+                Tags:      []*pb.Tag{},
+                Content:   "alice's event",
+                Sig:       "sig1",
+        }
+
+        err = store.StoreEvent(ctx, &EventData{
+                Event:         event,
+                CanonicalJSON: []byte(`[0,"alice",1234567890,1,[],"alice's event"]`),
+        })
+        if err != nil {
+                t.Fatalf("failed to store event: %v", err)
+        }
+
+        deletionEvent := &pb.Event{
+                Id:        "deletion456",
+                Pubkey:    "bob",
+                CreatedAt: time.Now().Unix(),
+                Kind:      KindDeletion,
+                Tags: []*pb.Tag{
+                        {Values: []string{"e", "event456"}},
+                },
+                Content: "trying to delete alice's event",
+                Sig:     "sig2",
+        }
+
+        err = store.ProcessDeletion(ctx, deletionEvent)
+        if err != nil {
+                t.Fatalf("process deletion should succeed but not delete: %v", err)
+        }
+
+        retrieved, err := store.GetEvent(ctx, "event456")
+        if err != nil {
+                t.Fatalf("event should still exist: %v", err)
+        }
+        if retrieved.Id != "event456" {
+                t.Errorf("expected event456, got %s", retrieved.Id)
+        }
+}
+
+func TestProcessDeletionMultipleEvents(t *testing.T) {
+        store, err := New(":memory:")
+        if err != nil {
+                t.Fatalf("failed to create storage: %v", err)
+        }
+        defer store.Close()
+
+        ctx := context.Background()
+
+        for i := 1; i <= 3; i++ {
+                event := &pb.Event{
+                        Id:        fmt.Sprintf("event%d", i),
+                        Pubkey:    "alice",
+                        CreatedAt: time.Now().Unix(),
+                        Kind:      1,
+                        Tags:      []*pb.Tag{},
+                        Content:   fmt.Sprintf("event %d", i),
+                        Sig:       fmt.Sprintf("sig%d", i),
+                }
+
+                err = store.StoreEvent(ctx, &EventData{
+                        Event:         event,
+                        CanonicalJSON: []byte(fmt.Sprintf(`[0,"alice",1234567890,1,[],"event %d"]`, i)),
+                })
+                if err != nil {
+                        t.Fatalf("failed to store event: %v", err)
+                }
+        }
+
+        deletionEvent := &pb.Event{
+                Id:        "deletion789",
+                Pubkey:    "alice",
+                CreatedAt: time.Now().Unix(),
+                Kind:      KindDeletion,
+                Tags: []*pb.Tag{
+                        {Values: []string{"e", "event1"}},
+                        {Values: []string{"e", "event2"}},
+                },
+                Content: "deleting multiple events",
+                Sig:     "sig_del",
+        }
+
+        err = store.ProcessDeletion(ctx, deletionEvent)
+        if err != nil {
+                t.Fatalf("failed to process deletion: %v", err)
+        }
+
+        _, err = store.GetEvent(ctx, "event1")
+        if err != ErrEventNotFound {
+                t.Error("event1 should be deleted")
+        }
+
+        _, err = store.GetEvent(ctx, "event2")
+        if err != ErrEventNotFound {
+                t.Error("event2 should be deleted")
+        }
+
+        _, err = store.GetEvent(ctx, "event3")
+        if err != nil {
+                t.Error("event3 should still exist")
+        }
+}