Add codex_hook_run analytics event (#17996)

# Why
Add product analytics for hook handler executions so we can understand
which hooks are running, where they came from, and whether they
completed, failed, stopped, or blocked work.

# What
- add the new `codex_hook_run` analytics event and payload plumbing in
`codex-rs/analytics`
- emit hook-run analytics from the shared hook completion path in
`codex-rs/core`
- classify hook source from the loaded hook path as `system`, `user`,
`project`, or `unknown`

```
{
  "event_type": "codex_hook_run",
  "event_params": {
    "thread_id": "string",
    "turn_id": "string",
    "model_slug": "string",
    "hook_name": "string, // any HookEventName
    "hook_source": "system | user | project | unknown",
    "status": "completed | failed | stopped | blocked"
  }
}
```

---------

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

codex-rs/protocol/src/protocol.rs

@@ -1635,6 +1635,20 @@ pub enum HookScope {
     Turn,
 }
 
+#[derive(Debug, Clone, Copy, Default, Deserialize, Serialize, PartialEq, Eq, JsonSchema, TS)]
+#[serde(rename_all = "snake_case")]
+pub enum HookSource {
+    System,
+    User,
+    Project,
+    Mdm,
+    SessionFlags,
+    LegacyManagedConfigFile,
+    LegacyManagedConfigMdm,
+    #[default]
+    Unknown,
+}
+
 #[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq, JsonSchema, TS)]
 #[serde(rename_all = "snake_case")]
 pub enum HookRunStatus {
@@ -1671,6 +1685,8 @@ pub struct HookRunSummary {
     pub execution_mode: HookExecutionMode,
     pub scope: HookScope,
     pub source_path: AbsolutePathBuf,
+    #[serde(default)]
+    pub source: HookSource,
     pub display_order: i64,
     pub status: HookRunStatus,
     pub status_message: Option<String>,