core: Organize runner components into runner_components module

Move runner state machine types and trigger runner into a dedicated
runner_components/ module to improve code organization:

- Move runner_state.rs -> runner_components/state.rs
- Move trigger_runner.rs -> runner_components/trigger_runner.rs
- Create runner_components/mod.rs with re-exports
- Update imports in runner.rs to use the new module path

This completes Phase 7 of the runner refactor plan.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: lutter

core/src/subgraph/mod.rs

@@ -5,11 +5,10 @@ mod instance_manager;
 mod loader;
 mod registrar;
 mod runner;
-mod runner_state;
+mod runner_components;
 mod state;
 mod stream;
 mod trigger_processor;
-mod trigger_runner;
 
 pub use self::instance_manager::SubgraphInstanceManager;
 pub use self::registrar::SubgraphRegistrar;

core/src/subgraph/runner.rs

@@ -4,10 +4,9 @@ use crate::subgraph::error::{
     ProcessingErrorKind,
 };
 use crate::subgraph::inputs::IndexingInputs;
-use crate::subgraph::runner_state::{RestartReason, RunnerState, StopReason};
+use crate::subgraph::runner_components::{RestartReason, RunnerState, StopReason, TriggerRunner};
 use crate::subgraph::state::IndexingState;
 use crate::subgraph::stream::new_block_stream;
-use crate::subgraph::trigger_runner::TriggerRunner;
 use anyhow::Context as _;
 use graph::blockchain::block_stream::{
     BlockStream, BlockStreamError, BlockStreamEvent, BlockWithTriggers, FirehoseCursor,

core/src/subgraph/runner_components/mod.rs

@@ -0,0 +1,13 @@
+//! SubgraphRunner components and state management.
+//!
+//! This module contains the state machine and helper components for the SubgraphRunner:
+//!
+//! - [`state`]: Defines [`RunnerState`], [`RestartReason`], and [`StopReason`] enums
+//!   that control the runner's lifecycle.
+//! - [`trigger_runner`]: Provides [`TriggerRunner`] for unified trigger execution.
+
+mod state;
+mod trigger_runner;
+
+pub use state::{RestartReason, RunnerState, StopReason};
+pub use trigger_runner::TriggerRunner;