Support MCP tools in hooks (#18385)

## Summary

Lifecycle hooks currently treat `PreToolUse`, `PostToolUse`, and
`PermissionRequest` as Bash-only flows
- hook schema constrains `tool_name` to `Bash`
- hook input assumes a command-shaped `tool_input`
- core hook dispatch path passes only shell command strings

That means hooks cannot target MCP tools even though MCP tool names are
model-visible and stable

This change generalizes those hook paths so they can match and receive
payloads for MCP tools while preserving the existing Bash behavior.

## Reviewer Notes

I think these are the key files
- `codex-rs/core/src/tools/handlers/mcp.rs`
- `codex-rs/core/src/mcp_tool_call.rs`

Otherwise the changes across apply_patch, shell, and unified_exec are
mainly to rewire everything to be `tool_input` based instead of just
`command` so that it'll make sense for MCP tools.

## Changes

- Allow `PreToolUse`, `PostToolUse`, and `PermissionRequest` hook inputs
to carry arbitrary `tool_name` and `tool_input` values instead of
hard-coding `Bash` and command-only payloads.
- Add MCP hook payload support through `McpHandler`, using the
model-visible tool name from `ToolInvocation` and the raw MCP arguments
as `tool_input`.
- Include MCP tool responses in `PostToolUse` by serializing
`McpToolOutput` into the hook response payload.
- Run `PermissionRequest` hooks for MCP approval requests after
remembered approval checks and before falling back to user-facing MCP
elicitation.
- Preserve exact matching for literal hook matchers like `Bash` and
`mcp__memory__create_entities`, while keeping regex matcher support for
patterns like `mcp__memory__.*` and `mcp__.*__write.*`.

---------

Co-authored-by: Andrei Eternal <eternal@openai.com>
Co-authored-by: Codex <noreply@openai.com>

codex-rs/app-server/tests/suite/v2/realtime_conversation.rs

@@ -72,6 +72,7 @@ use wiremock::matchers::path;
 use wiremock::matchers::path_regex;
 
 const DEFAULT_TIMEOUT: Duration = Duration::from_secs(10);
+const DELEGATED_SHELL_TOOL_TIMEOUT_MS: u64 = 30_000;
 const STARTUP_CONTEXT_HEADER: &str = "Startup context from Codex.";
 const V2_STEERING_ACKNOWLEDGEMENT: &str =
     "This was sent to steer the previous background agent task.";
@@ -1781,7 +1782,9 @@ async fn webrtc_v2_tool_call_delegated_turn_can_execute_shell_tool() -> Result<(
         create_shell_command_sse_response(
             realtime_tool_ok_command(),
             /*workdir*/ None,
-            Some(5000),
+            // Windows CI can spend several seconds starting the nested PowerShell command. This
+            // test verifies delegated shell-tool plumbing, not timeout enforcement.
+            Some(DELEGATED_SHELL_TOOL_TIMEOUT_MS),
             "shell_call",
         )?,
         create_final_assistant_message_sse_response("shell tool finished")?,