refactor: simplify deletion handling (remove NIP-09 processing)

Remove deletion processing logic in favor of simpler approach:
- Remove deletions table from schema
- Delete deletions.go and deletions_test.go
- Remove ProcessDeletion from EventStore interface
- Kind 5 events now stored like any other event (no special handling)
- Update storage test to expect 2 tables instead of 3
- All 41 tests passing

1 files changed, 0 insertions, 1 deletions

diff --git a/README.md b/README.md
index d2fbd41..61fa0d4 100644
--- a/README.md
+++ b/README.md
@@ -100,7 +100,6 @@ See [proto/nostr/v1/nostr.proto](proto/nostr/v1/nostr.proto) for the full API.
   - **WebSocket** (NIP-01 - standard Nostr protocol)
 - ✅ Subscribe/streaming (real-time event delivery)
 - ✅ Subscription management (filter matching, fan-out)
-- ✅ **NIP-09** - Event deletion (authors can delete their own events)
 - ✅ **NIP-11** - Relay info document (GET with `Accept: application/nostr+json`)
 
 **Compatible with:**