chore: merge rename commit into Plan 1B branch

Resolves conflicts from merging origin/main (idfoto→relicario rename):
- Kept Plan 1A's typed-item vault.rs, lib.rs, integration.rs over main's
  old entry-based versions
- Took main's relicario_dir() fix in CLI main.rs (sed had missed idfoto_dir)
- Kept Plan 1A's UnsupportedFormatVersion error variant in crypto.rs
- Kept Plan 1A's opaque Decrypt message (audit M4) in error.rs
- Deleted entry.rs (replaced by item.rs + typed modules in Plan 1A)
- Resolved Cargo.toml description to main's "relicario password manager"

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

crates/relicario-core/src/crypto.rs

@@ -298,7 +298,7 @@ mod tests {
     #[test]
     fn encrypt_decrypt_round_trip() {
         let key = [0xABu8; 32];
-        let plaintext = b"hello, idfoto!";
+        let plaintext = b"hello, relicario!";
 
         let ciphertext = encrypt(&key, plaintext).unwrap();
         let decrypted = decrypt(&key, &ciphertext).unwrap();