feat(tasks): B2a part 1 — archive schema + task_lists scaffolding

Migration v16 adds tasks.archived (default 0) + tasks.archived_at +
idx_tasks_archived. TaskRow extended with both fields; list_tasks and
list_subtasks default-filter archived rows; complete_subtask_and_check_parent
SELECT lists updated to round-trip the new columns. TaskListRow +
ImportSummary structs land in preparation for the task_lists CRUD
that part 2 wires up. All 61 existing tests still pass.

(SQL splitter is naive about ';' inside -- comments, so the v16
comment block was rewritten to avoid a bare semicolon mid-comment
that the splitter was treating as a statement boundary.)

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

crates/storage/src/database.rs

@@ -328,8 +328,9 @@ pub async fn insert_task(
 pub async fn list_tasks(pool: &SqlitePool) -> Result<Vec<TaskRow>> {
     let rows = sqlx::query(
         "SELECT id, text, bucket, list_id, effort, notes, done, done_at, created_at, \
-         source_transcript_id, parent_task_id, energy \
-         FROM tasks WHERE parent_task_id IS NULL ORDER BY created_at DESC",
+         source_transcript_id, parent_task_id, energy, archived, archived_at \
+         FROM tasks WHERE parent_task_id IS NULL AND archived = 0 \
+         ORDER BY created_at DESC",
     )
     .fetch_all(pool)
     .await
@@ -341,7 +342,8 @@ pub async fn list_tasks(pool: &SqlitePool) -> Result<Vec<TaskRow>> {
 pub async fn get_task_by_id(pool: &SqlitePool, id: &str) -> Result<Option<TaskRow>> {
     let row = sqlx::query(
         "SELECT id, text, bucket, list_id, effort, notes, done, done_at, created_at, \
-         source_transcript_id, parent_task_id, energy FROM tasks WHERE id = ?",
+         source_transcript_id, parent_task_id, energy, archived, archived_at \
+         FROM tasks WHERE id = ?",
     )
     .bind(id)
     .fetch_optional(pool)
@@ -431,8 +433,8 @@ pub async fn insert_subtask(
 pub async fn list_subtasks(pool: &SqlitePool, parent_id: &str) -> Result<Vec<TaskRow>> {
     let rows = sqlx::query(
         "SELECT id, text, bucket, list_id, effort, notes, done, done_at, created_at, \
-         source_transcript_id, parent_task_id, energy \
-         FROM tasks WHERE parent_task_id = ? ORDER BY created_at ASC",
+         source_transcript_id, parent_task_id, energy, archived, archived_at \
+         FROM tasks WHERE parent_task_id = ? AND archived = 0 ORDER BY created_at ASC",
     )
     .bind(parent_id)
     .fetch_all(pool)
@@ -499,7 +501,8 @@ pub async fn complete_subtask_and_check_parent(
     }
 
     let select_sql = "SELECT id, text, bucket, list_id, effort, notes, done, done_at, \
-        created_at, source_transcript_id, parent_task_id, energy FROM tasks WHERE id = ?";
+        created_at, source_transcript_id, parent_task_id, energy, archived, archived_at \
+        FROM tasks WHERE id = ?";
 
     let updated_subtask = sqlx::query(select_sql)
         .bind(subtask_id)
@@ -872,6 +875,34 @@ pub struct TaskRow {
     /// migration v11). Unset is the expected normal case — the match-my-
     /// energy sort treats unset as Medium-equivalent.
     pub energy: Option<String>,
+    /// B2a — Inbox-only archive flag (migration v16). `true` means the
+    /// row is archived and excluded from the default `list_tasks` /
+    /// `list_subtasks` query. `archived_at` stamps the archive time so
+    /// the Archived view can sort newest-first.
+    pub archived: bool,
+    pub archived_at: Option<String>,
+}
+
+/// B2a — task_lists row. Mirrors the `task_lists` table that has lived in
+/// migration v1 since the start; this struct + the surrounding CRUD wires
+/// the table that the frontend was previously stashing in localStorage.
+#[derive(Debug, Clone)]
+pub struct TaskListRow {
+    pub id: String,
+    pub name: String,
+    pub built_in: bool,
+    pub profile_id: Option<String>,
+    pub created_at: String,
+}
+
+/// Result of `import_task_lists` — how many rows landed and how many were
+/// skipped because their `id` already exists. The whole batch runs in one
+/// transaction so a duplicate inside the batch (rather than against the
+/// existing table) is a hard failure that rolls everything back.
+#[derive(Debug, Clone)]
+pub struct ImportSummary {
+    pub imported: usize,
+    pub skipped: usize,
 }
 
 #[derive(Debug, Clone)]
@@ -948,6 +979,18 @@ fn task_row_from(r: sqlx::sqlite::SqliteRow) -> TaskRow {
         source_transcript_id: r.get("source_transcript_id"),
         parent_task_id: r.get("parent_task_id"),
         energy: r.get("energy"),
+        archived: r.get::<i64, _>("archived") != 0,
+        archived_at: r.get("archived_at"),
+    }
+}
+
+fn task_list_row_from(r: &sqlx::sqlite::SqliteRow) -> TaskListRow {
+    TaskListRow {
+        id: r.get("id"),
+        name: r.get("name"),
+        built_in: r.get::<i64, _>("built_in") != 0,
+        profile_id: r.get("profile_id"),
+        created_at: r.get("created_at"),
     }
 }