Add Programmer Tasks module (work-log + time tracking)

Separate feature for the `programmer` role to record dev work by category,
distinct from the IT help-desk `tasks` feature. Modeled on the IT Service
Requests pattern (Brick offline-first model -> Riverpod stream/controller ->
list/detail screens); seed of a future Project Management workflow.

- programmer_tasks + programmer_task_activity_logs (category enum, RLS,
  realtime) via supabase migration
- single assignee, self-logged or lead-assigned; assign/reassign logged
- pause-on-switch: starting a task while another runs prompts to pause the
  running one, keeping one active task per user for accurate time attribution
- worked-duration math shared with help-desk tasks via a generic core in
  task_duration.dart (existing callers unchanged)
- list distinguishes running vs paused with a per-task Resume shortcut
- accessible dialog labels; route /programmer-tasks + nav gated to admin/programmer
- unit/widget tests: controller lifecycle, duration math, pause-switch dialog

Co-Authored-By: claude-flow <ruv@ruv.net>

lib/brick/db/schema.g.dart

@@ -1,11 +1,13 @@
 // GENERATED CODE DO NOT EDIT
 // This file should be version controlled
 import 'package:brick_sqlite/db.dart';
+part '20260926162926.migration.dart';
 part '20260411041808.migration.dart';
 part '20260411042152.migration.dart';
 
 /// All intelligently-generated migrations from all `@Migratable` classes on disk
 final migrations = <Migration>{
+  const Migration20260926162926(),
   const Migration20260411041808(),
   const Migration20260411042152(),
 };
@@ -334,6 +336,53 @@ final schema = Schema(
       },
       indices: <SchemaIndex>{},
     ),
+    SchemaTable(
+      'ProgrammerTask',
+      columns: <SchemaColumn>{
+        SchemaColumn(
+          '_brick_id',
+          Column.integer,
+          autoincrement: true,
+          nullable: false,
+          isPrimaryKey: true,
+        ),
+        SchemaColumn('id', Column.varchar),
+        SchemaColumn('title', Column.varchar),
+        SchemaColumn('description', Column.varchar),
+        SchemaColumn('category', Column.varchar),
+        SchemaColumn('status', Column.varchar),
+        SchemaColumn('priority', Column.integer),
+        SchemaColumn('assignee_id', Column.varchar),
+        SchemaColumn('creator_id', Column.varchar),
+        SchemaColumn('created_at', Column.datetime),
+        SchemaColumn('started_at', Column.datetime),
+        SchemaColumn('completed_at', Column.datetime),
+        SchemaColumn('cancelled_at', Column.datetime),
+        SchemaColumn('cancellation_reason', Column.varchar),
+        SchemaColumn('updated_at', Column.datetime),
+        SchemaColumn('is_terminal', Column.boolean),
+      },
+      indices: <SchemaIndex>{},
+    ),
+    SchemaTable(
+      'ProgrammerTaskActivityLog',
+      columns: <SchemaColumn>{
+        SchemaColumn(
+          '_brick_id',
+          Column.integer,
+          autoincrement: true,
+          nullable: false,
+          isPrimaryKey: true,
+        ),
+        SchemaColumn('id', Column.varchar),
+        SchemaColumn('task_id', Column.varchar),
+        SchemaColumn('actor_id', Column.varchar),
+        SchemaColumn('action_type', Column.varchar),
+        SchemaColumn('meta', Column.varchar),
+        SchemaColumn('created_at', Column.datetime),
+      },
+      indices: <SchemaIndex>{},
+    ),
     SchemaTable(
       'Service',
       columns: <SchemaColumn>{