Homepage JSON returns databases as a list

/.json previously returned databases as an object keyed by database
name, unlike /-/databases.json and every other collection in the API.
It now returns a list of database objects. The HTML template already
consumed the list. This endpoint remains undocumented.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GrHZSypDfMnym1tM5XJAFZ

existing-api.md

@@ -201,8 +201,8 @@ Routes: `/(\.(?P<format>jsono?))?$` and `/-/(\.(?P<format>jsono?))?$`
 - **Parameters:** `_sort=relationships` sorts each database's truncated table
   list by foreign-key relationship count.
 - **JSON response** (index.py:147-161) — includes `ok: true` plus:
-  - `databases` — an **object keyed by database name** (not a list). Each
-    value: `name`, `hash` (or null), `color`, `path`,
+  - `databases` — a **list** of database objects (undocumented API, subject
+    to change). Each item: `name`, `hash` (or null), `color`, `path`,
     `tables_and_views_truncated` (up to 5 items: `name`, `columns`,
     `primary_keys`, `count` (int or null), `hidden`, `fts_table`,
     `num_relationships_for_sorting`, `private`; view items are just