Phase 7: MCP handler (25 tests), NIP-04 encrypt/decrypt (15 tests), CVM server skeleton

- mcp_handler.c/h: 4 tools (get_config, set_config, get_balance, wallet_send)
- nip04.c/h: AES-256-CBC + ECDH with 0x02 compressed pubkey prefix
  - Fixed IV copy bug: mbedTLS AES-CBC modifies IV in-place
  - Base64 encode/decode for ciphertext transport
  - PKCS7 padding
- cvm_server.c/h: Nostr DM listener with FreeRTOS task
- config: cvm_enabled, cvm_relays fields
- 156 total tests passing across 10 test binaries

1 files changed, 3 insertions, 0 deletions

diff --git a/main/CMakeLists.txt b/main/CMakeLists.txt
index c2aaeb2..91748f2 100644
--- a/main/CMakeLists.txt
+++ b/main/CMakeLists.txt
@@ -13,6 +13,9 @@ idf_component_register(SRCS "tollgate_main.c"
                             "tollgate_client.c"
                             "lnurl_pay.c"
                             "lightning_payout.c"
+                            "nip04.c"
+                            "mcp_handler.c"
+                            "cvm_server.c"
                     INCLUDE_DIRS "."
                     REQUIRES esp_wifi esp_event esp_netif nvs_flash esp_http_server
                              lwip json esp_http_client mbedtls esp-tls log spiffs