refactor: rename DTree to DValue

site/doc/pages/sqlite_query.txt

@@ -1,12 +1,12 @@
 :sig
-DTree sqlite_query(SQLite* db, String q)
-DTree sqlite_query(SQLite* db, String q, StringMap params)
+DValue sqlite_query(SQLite* db, String q)
+DValue sqlite_query(SQLite* db, String q, StringMap params)
 
 :params
 db : pointer to an active SQLite connection
 q : SQL statement
 params : optional named parameter map
-return value : list of result rows as a DTree
+return value : list of result rows as a DValue
 
 :see
 >sqlite
@@ -14,10 +14,10 @@ sqlite_connect
 sqlite_error
 sqlite_insert_id
 sqlite_affected_rows
-0_DTree
+0_DValue
 
 :content
-Executes one SQLite statement and returns result rows as a `DTree` array. Multi-statement SQL strings are rejected so migrations cannot silently run only their first statement.
+Executes one SQLite statement and returns result rows as a `DValue` array. Multi-statement SQL strings are rejected so migrations cannot silently run only their first statement.
 
 Use named parameters with `:name` placeholders only. Positional `?` placeholders and SQLite's other named marker forms (`@name`, `$name`) are rejected so UCE SQLite queries use the same placeholder style as the MySQL helper. UCE binds parameters with SQLite prepared statements; it does not substitute values into the SQL string.
 
@@ -26,12 +26,12 @@ SQLite* db = sqlite_connect("/tmp/app.sqlite");
 
 StringMap params;
 params["email"] = "ada@example.test";
-DTree rows = sqlite_query(db,
+DValue rows = sqlite_query(db,
     "select id, email from users where email = :email",
     params
 );
 ```
 
-Result rows are objects keyed by column name. SQLite integer, float, text, blob, and null values are converted to DTree values. Blob values are returned as byte strings.
+Result rows are objects keyed by column name. SQLite integer, float, text, blob, and null values are converted to DValue values. Blob values are returned as byte strings.
 
 For statements that do not return rows, inspect `sqlite_affected_rows()` or `sqlite_insert_id()` after the call.