feat(api): add activities + work_sessions domain schema and shared contracts

apps/api/src/db/schema.ts

@@ -109,3 +109,45 @@ export const accountRelations = relations(account, ({ one }) => ({
     references: [user.id],
   }),
 }));
+
+// ---- SoleLog domain tables (Phase 1) ----
+export const activities = sqliteTable('activities', {
+  id: integer('id').primaryKey({ autoIncrement: true }),
+  name: text('name').notNull(),
+  // subset of 'Kurk' | 'Berk' | '3D' — stored as a JSON string by libsql.
+  insoleTypes: text('insole_types', { mode: 'json' })
+    .$type<string[]>()
+    .notNull()
+    .default(['Kurk', 'Berk', '3D']),
+  createdAt: integer('created_at', { mode: 'timestamp_ms' })
+    .default(sql`(cast(unixepoch('subsecond') * 1000 as integer))`)
+    .notNull(),
+});
+
+export const workSessions = sqliteTable(
+  'work_sessions',
+  {
+    id: integer('id').primaryKey({ autoIncrement: true }),
+    userId: text('user_id')
+      .notNull()
+      .references(() => user.id, { onDelete: 'cascade' }),
+    activityId: integer('activity_id')
+      .notNull()
+      .references(() => activities.id),
+    insoleType: text('insole_type'),
+    pairCount: integer('pair_count').notNull().default(2),
+    startTime: integer('start_time', { mode: 'timestamp_ms' }).notNull(),
+    endTime: integer('end_time', { mode: 'timestamp_ms' }), // null = active
+    durationSeconds: integer('duration_seconds'),
+    status: text('status').notNull().default('active'), // 'active' | 'completed' | 'discarded'
+    source: text('source').notNull().default('app'), // 'app' | 'manual'
+    notes: text('notes'),
+    createdAt: integer('created_at', { mode: 'timestamp_ms' })
+      .default(sql`(cast(unixepoch('subsecond') * 1000 as integer))`)
+      .notNull(),
+  },
+  (table) => ({
+    workSessionsUserIdIdx: index('work_sessions_userId_idx').on(table.userId),
+    workSessionsStartTimeIdx: index('work_sessions_startTime_idx').on(table.startTime),
+  })
+);