[codex-analytics] emit goal lifecycle analytics (#27078)

## Why
- Currently, there is no analytics event for `/goal` behavior
- Existing events cannot identify goal execution or its resulting
outcome
- The original update in
[#26182](https://github.com/openai/codex/pull/26182) was implemented
before `/goal` moved into `codex-goal-extension`.

## What Changed
- Adds `codex_goal_event` serialization and enrichment to
`codex-analytics`
- Emits goal events from the canonical `codex-goal-extension` mutation
and accounting paths:
  - `created` when a new logical goal is persisted
  - `usage_accounted` when cumulative goal usage is persisted
  - `status_changed` when the stored goal status changes
  - `cleared` when the goal is deleted
- Preserves causal `turn_id` for turn driven events and uses null
attribution for external or idle lifecycle events
- Changes goal deletion to return the deleted row so `cleared` retains
the stable goal ID

## Event Details

Includes standard analytics metadata along with goal specific fields:
- `goal_id`: Stable ID stored in the local SQLite goal row and shared
across the goal's events
- `event_kind`: Observed operation (see the 4 lifecycle events cited in
the above bullet)
- `goal_status`: Resulting or last stored status: `active`, `paused`,
`blocked`, `usage_limited`, etc.
  - `has_token_budget`: Indicates whether a token budget is configured
  - `turn_id`: Causal turn ID, or null when no causal turn exists
- `cumulative_tokens_accounted`: Cumulative tokens on `usage_accounted`
events; null otherwise
- `cumulative_time_accounted_seconds`: Cumulative active time on
`usage_accounted` events; null otherwise

## Validation
- `just test -p codex-analytics -p codex-state -p codex-goal-extension`
- `just test -p codex-core -E 'test(/goal/)'`
- `just test -p codex-app-server`
- `cargo build -p codex-analytics -p codex-core -p codex-state -p
codex-app-server`

codex-rs/ext/goal/src/tool.rs

@@ -17,6 +17,8 @@ use serde::Serialize;
 
 use crate::accounting::BudgetLimitedGoalDisposition;
 use crate::accounting::GoalAccountingState;
+use crate::analytics::GoalAnalytics;
+use crate::analytics::GoalEventAttribution;
 use crate::events::GoalEventEmitter;
 use crate::metrics::GoalMetrics;
 use crate::spec::CREATE_GOAL_TOOL_NAME;
@@ -32,6 +34,7 @@ pub(crate) struct GoalToolExecutor {
     thread_id: ThreadId,
     state_db: Arc<codex_state::StateRuntime>,
     accounting_state: Arc<GoalAccountingState>,
+    analytics: GoalAnalytics,
     event_emitter: GoalEventEmitter,
     metrics: GoalMetrics,
 }
@@ -75,6 +78,7 @@ impl GoalToolExecutor {
         thread_id: ThreadId,
         state_db: Arc<codex_state::StateRuntime>,
         accounting_state: Arc<GoalAccountingState>,
+        analytics: GoalAnalytics,
         event_emitter: GoalEventEmitter,
         metrics: GoalMetrics,
     ) -> Self {
@@ -83,6 +87,7 @@ impl GoalToolExecutor {
             thread_id,
             state_db,
             accounting_state,
+            analytics,
             event_emitter,
             metrics,
         }
@@ -92,6 +97,7 @@ impl GoalToolExecutor {
         thread_id: ThreadId,
         state_db: Arc<codex_state::StateRuntime>,
         accounting_state: Arc<GoalAccountingState>,
+        analytics: GoalAnalytics,
         event_emitter: GoalEventEmitter,
         metrics: GoalMetrics,
     ) -> Self {
@@ -100,6 +106,7 @@ impl GoalToolExecutor {
             thread_id,
             state_db,
             accounting_state,
+            analytics,
             event_emitter,
             metrics,
         }
@@ -109,6 +116,7 @@ impl GoalToolExecutor {
         thread_id: ThreadId,
         state_db: Arc<codex_state::StateRuntime>,
         accounting_state: Arc<GoalAccountingState>,
+        analytics: GoalAnalytics,
         event_emitter: GoalEventEmitter,
         metrics: GoalMetrics,
     ) -> Self {
@@ -117,6 +125,7 @@ impl GoalToolExecutor {
             thread_id,
             state_db,
             accounting_state,
+            analytics,
             event_emitter,
             metrics,
         }
@@ -200,6 +209,10 @@ impl GoalToolExecutor {
             .accounting_state
             .mark_current_turn_goal_active(goal.goal_id.clone());
         self.metrics.record_created();
+        self.analytics.created(
+            &goal,
+            GoalEventAttribution::Turn(invocation.turn_id.as_str()),
+        );
         let goal = protocol_goal_from_state(goal);
         self.emit_goal_updated_from_tool_call(&invocation, turn_id, goal.clone());
         goal_response(Some(goal), CompletionBudgetReport::Omit)
@@ -259,6 +272,11 @@ impl GoalToolExecutor {
             })?;
         self.metrics
             .record_terminal_if_status_changed(previous_status, &goal);
+        self.analytics.status_changed(
+            &goal,
+            previous_status,
+            GoalEventAttribution::Turn(invocation.turn_id.as_str()),
+        );
         let goal = protocol_goal_from_state(goal);
         let turn_id = self.accounting_state.clear_current_turn_goal();
         self.emit_goal_updated_from_tool_call(&invocation, turn_id, goal.clone());
@@ -324,6 +342,13 @@ impl GoalToolExecutor {
             codex_state::GoalAccountingOutcome::Updated(goal) => {
                 self.metrics
                     .record_terminal_if_status_changed(previous_status, &goal);
+                self.analytics
+                    .usage_accounted(&goal, GoalEventAttribution::Turn(turn_id.as_str()));
+                self.analytics.status_changed(
+                    &goal,
+                    previous_status,
+                    GoalEventAttribution::Turn(turn_id.as_str()),
+                );
                 self.accounting_state.mark_progress_accounted_for_status(
                     turn_id.as_str(),
                     &snapshot,