chore: upgrade rmcp crate from 0.10.0 to 0.12.0 (#8288)

Version `0.12.0` includes
https://github.com/modelcontextprotocol/rust-sdk/pull/590, which I will
use in https://github.com/openai/codex/pull/8142.

Changes:

- `rmcp::model::CustomClientNotification` was renamed to
`rmcp::model::CustomNotification`
- a bunch of types have a `meta` field now, but it is `Option`, so I
added `meta: None` to a bunch of things

codex-rs/Cargo.lock

@@ -2206,6 +2206,16 @@ dependencies = [
  "darling_macro 0.21.3",
 ]
 
+[[package]]
+name = "darling"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25ae13da2f202d56bd7f91c25fba009e7717a1e4a1cc98a76d844b65ae912e9d"
+dependencies = [
+ "darling_core 0.23.0",
+ "darling_macro 0.23.0",
+]
+
 [[package]]
 name = "darling_core"
 version = "0.20.11"
@@ -2234,6 +2244,19 @@ dependencies = [
  "syn 2.0.104",
 ]
 
+[[package]]
+name = "darling_core"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9865a50f7c335f53564bb694ef660825eb8610e0a53d3e11bf1b0d3df31e03b0"
+dependencies = [
+ "ident_case",
+ "proc-macro2",
+ "quote",
+ "strsim 0.11.1",
+ "syn 2.0.104",
+]
+
 [[package]]
 name = "darling_macro"
 version = "0.20.11"
@@ -2256,6 +2279,17 @@ dependencies = [
  "syn 2.0.104",
 ]
 
+[[package]]
+name = "darling_macro"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3984ec7bd6cfa798e62b4a642426a5be0e68f9401cfc2a01e3fa9ea2fcdb8d"
+dependencies = [
+ "darling_core 0.23.0",
+ "quote",
+ "syn 2.0.104",
+]
+
 [[package]]
 name = "dbus"
 version = "0.9.9"
@@ -5072,9 +5106,9 @@ dependencies = [
 
 [[package]]
 name = "process-wrap"
-version = "8.2.1"
+version = "9.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a3ef4f2f0422f23a82ec9f628ea2acd12871c81a9362b02c43c1aa86acfc3ba1"
+checksum = "5e5fd83ab7fa55fd06f5e665e3fc52b8bca451c0486b8ea60ad649cd1c10a5da"
 dependencies = [
  "futures",
  "indexmap 2.12.0",
@@ -5484,9 +5518,9 @@ dependencies = [
 
 [[package]]
 name = "rmcp"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "38b18323edc657390a6ed4d7a9110b0dec2dc3ed128eb2a123edfbafabdbddc5"
+checksum = "528d42f8176e6e5e71ea69182b17d1d0a19a6b3b894b564678b74cd7cab13cfa"
 dependencies = [
  "async-trait",
  "base64",
@@ -5519,11 +5553,11 @@ dependencies = [
 
 [[package]]
 name = "rmcp-macros"
-version = "0.10.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c75d0a62676bf8c8003c4e3c348e2ceb6a7b3e48323681aaf177fdccdac2ce50"
+checksum = "e3f81daaa494eb8e985c9462f7d6ce1ab05e5299f48aafd76cdd3d8b060e6f59"
 dependencies = [
- "darling 0.21.3",
+ "darling 0.23.0",
  "proc-macro2",
  "quote",
  "serde_json",