Collections Phase 1: Foundation

Make folders into first-class collection objects via `__collection.yaml` and add basic list/table views.

Scope

IndexManager recognizes `__collection.yaml` files during sync

Creates a `collection` entry in the index (type: collection)

Fields: title, description, tags, icon, source (folder/query), view preferences

`collection` added to built-in entry types in `ENTRY_TYPE_REGISTRY`

Collection is an entry with extra fields: `source_type` (folder/query), `view_config` (JSON), `entry_filter` (JSON)

Folder collections automatically include entries in that directory

`GET /api/collections` — list all collections

`GET /api/collections/{id}/entries` — list entries in a collection

`list` view — simple entry list with title, date, type badge (default)

`table` view — columnar view with sortable headers, configurable visible fields

View switcher component to toggle between views

New route: `/collections/{id}` page

Folders without `__collection.yaml` work exactly as before

No schema changes to existing tables — collections are regular entries

Virtual collections / query DSL (Phase 2)

Kanban, gallery, timeline views (Phase 3)

Transclusion embedding (Phase 4)

Plugin collection types (Phase 5)