chore: move mcp-server/src/wire_format.rs to protocol/src/mcp_protocol.rs (#2423)

The existing `wire_format.rs` should share more types with the
`codex-protocol` crate (like `AskForApproval` instead of maintaining a
parallel `CodexToolCallApprovalPolicy` enum), so this PR moves
`wire_format.rs` into `codex-protocol`, renaming it as
`mcp-protocol.rs`. We also de-dupe types, where appropriate.

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[//]: # (BEGIN SAPLING FOOTER)
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* #2424
* __->__ #2423

codex-rs/tui/src/lib.rs

@@ -10,11 +10,11 @@ use codex_core::config::ConfigOverrides;
 use codex_core::config::ConfigToml;
 use codex_core::config::find_codex_home;
 use codex_core::config::load_config_as_toml_with_cli_overrides;
-use codex_core::config_types::SandboxMode;
 use codex_core::protocol::AskForApproval;
 use codex_core::protocol::SandboxPolicy;
 use codex_login::CodexAuth;
 use codex_ollama::DEFAULT_OSS_MODEL;
+use codex_protocol::config_types::SandboxMode;
 use std::fs::OpenOptions;
 use std::path::PathBuf;
 use tracing::error;