feat(ui): add maintenance page for task management

* Implement maintenance page with task and log display
* Add backfill and metadata retry functionality
* Integrate grid component for project display in thoughts page
* Update types for maintenance tasks and logs
* Enhance sidebar and shell for new maintenance navigation

migrations/_old/019_tool_annotations.sql

@@ -0,0 +1,14 @@
+-- Migration: 019_tool_annotations
+-- Adds a table for model-authored usage notes per tool.
+
+create table if not exists tool_annotations (
+  id         bigserial   primary key,
+  tool_name  text        not null,
+  notes      text        not null default '',
+  created_at timestamptz not null default now(),
+  updated_at timestamptz not null default now(),
+  constraint tool_annotations_tool_name_unique unique (tool_name)
+);
+
+grant all on table public.tool_annotations to amcs;
+grant usage, select on sequence tool_annotations_id_seq to amcs;