## ADDED Requirements

### Requirement: Per-step timeline persistence
The system SHALL persist a record for every step of a task, containing the screenshot, the Scene JSON, the prompt/goal context, the tool call issued, and its result, written to local storage under a task-specific path.

#### Scenario: Step record written after each action
- **WHEN** the Executor completes a step (successful or failed)
- **THEN** the system writes that step's screenshot and a JSON record (Scene, prompt, tool call, result) to the task's timeline directory before proceeding to the next step

#### Scenario: Timeline survives process restart
- **WHEN** the process running a task restarts after a step has already been persisted
- **THEN** the previously persisted steps for that task remain readable from disk

### Requirement: Task metadata storage
The system SHALL store task-level metadata (task id, target device id, status, start/end timestamps) in a local database (SQLite for this change), separate from the per-step image/JSON artifacts on the filesystem.

#### Scenario: Task status queryable during execution
- **WHEN** a caller queries a task by id while it is still running
- **THEN** the system returns its current status (e.g. `running`) and metadata without needing to scan the filesystem timeline

#### Scenario: Task status reflects completion
- **WHEN** a task finishes (successfully or with failure)
- **THEN** its stored metadata status is updated accordingly and its end timestamp is recorded

### Requirement: Timeline retrievable for future replay
The system SHALL store each task's steps in a way that preserves their order and completeness, so that a future replay feature can reconstruct the full sequence of screenshots/Scenes/actions for a task without additional data collection.

#### Scenario: Steps retrievable in order
- **WHEN** a caller requests the full timeline for a completed task
- **THEN** the system returns all persisted steps in the order they occurred, each with its screenshot and JSON record