feat: add NIP-04 and NIP-44 encrypt/decrypt RPC endpoints for iframe apps

Backend: identity.nostr-encrypt-nip04, identity.nostr-decrypt-nip04,
identity.nostr-encrypt-nip44, identity.nostr-decrypt-nip44 endpoints
with auto-resolve to default identity. Frontend: appLauncher routes
nip04.* and nip44.* postMessage calls to backend RPC.

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

neode-ui/src/stores/appLauncher.ts

@@ -218,6 +218,30 @@ export const useAppLauncherStore = defineStore('appLauncher', () => {
         result = res
       } else if (method === 'getRelays') {
         result = {}
+      } else if (method === 'nip04.encrypt') {
+        const res = await rpcClient.call<{ ciphertext: string }>({
+          method: 'identity.nostr-encrypt-nip04',
+          params: { pubkey: params.pubkey, plaintext: params.plaintext }
+        })
+        result = res.ciphertext
+      } else if (method === 'nip04.decrypt') {
+        const res = await rpcClient.call<{ plaintext: string }>({
+          method: 'identity.nostr-decrypt-nip04',
+          params: { pubkey: params.pubkey, ciphertext: params.ciphertext }
+        })
+        result = res.plaintext
+      } else if (method === 'nip44.encrypt') {
+        const res = await rpcClient.call<{ ciphertext: string }>({
+          method: 'identity.nostr-encrypt-nip44',
+          params: { pubkey: params.pubkey, plaintext: params.plaintext }
+        })
+        result = res.ciphertext
+      } else if (method === 'nip44.decrypt') {
+        const res = await rpcClient.call<{ plaintext: string }>({
+          method: 'identity.nostr-decrypt-nip44',
+          params: { pubkey: params.pubkey, ciphertext: params.ciphertext }
+        })
+        result = res.plaintext
       } else {
         throw new Error(`Unsupported NIP-07 method: ${method}`)
       }