Adv 2.0 L5d: streak/action/lifecycle migration off AdvCharacter

Ten player_meta columns: current_streak, best_streak, last_action_date,
streak_decayed, action_taken_today, holiday_action_taken,
combat_actions_used, harvest_actions_used, created_at, last_active_at.

LifecycleState struct with HasLifecycle() marker + load/upsert/backfill/
projection helpers. New resetAllPlayerMetaDailyActions parallels the
existing resetAllAdvDailyActions for the bulk midnight reset.

createAdvCharacter now seeds created_at/last_active_at (CURRENT_TIMESTAMP)
so player_meta rows are fully formed at creation.

Mutation surface turned out to be small: only `rest` writes
ActionTakenToday (combat/harvest counters are dormant in current code);
plus streak halve + streak update in scheduler. Dual-writes wired at all
four sites + the bulk reset.

Tests: TestPlayerMetaLifecycleStateBackfill_Idempotent,
TestLoadLifecycleState_FallsBackToAdvCharacter,
TestUpsertPlayerMetaLifecycleState_RoundTrip,
TestResetAllPlayerMetaDailyActions.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/plugin/adventure_character.go

@@ -559,9 +559,12 @@ func createAdvCharacter(userID id.UserID, displayName string) error {
 	}
 
 	// Adv 2.0 Phase L4f-prep — dual-write display_name into player_meta.
+	// Adv 2.0 Phase L5d — also seed created_at + last_active_at lifecycle
+	// timestamps so the player_meta row is fully formed at creation.
 	// Inside the same tx so the two rows are created atomically.
 	if _, err = tx.Exec(
-		`INSERT INTO player_meta (user_id, display_name) VALUES (?, ?)
+		`INSERT INTO player_meta (user_id, display_name, created_at, last_active_at)
+		 VALUES (?, ?, CURRENT_TIMESTAMP, CURRENT_TIMESTAMP)
 		 ON CONFLICT(user_id) DO UPDATE SET display_name = excluded.display_name`,
 		string(userID), displayName,
 	); err != nil {