docs: Clarify dialect & target in book (#1521)

* docs: Clarify dialect & target in book

Author: max-sixty

book/src/SUMMARY.md

@@ -8,7 +8,7 @@
   - [Functions](./queries/functions.md)
   - [Tables](./queries/tables.md)
   - [Syntax](./queries/syntax.md)
-  - [Dialect & version](./queries/dialect-and-version.md)
+  - [Header: target & version](./queries/header.md)
 - [Transforms](./transforms.md)
   - [Aggregate](./transforms/aggregate.md)
   - [Append](./transforms/append.md)

book/src/queries/dialect-and-version.md renamed to book/src/queries/header.md

@@ -1,7 +1,7 @@
 ---
 source: book/tests/snapshot.rs
 expression: "prql target:sql.postgres\n\nfrom employees\nsort age\ntake 10\n"
-input_file: book/tests/prql/queries/dialect-and-version-0.prql
+input_file: book/tests/prql/queries/header-0.prql
 ---
 SELECT
   *

book/tests/prql/queries/dialect-and-version-0.prql renamed to book/tests/prql/queries/header-0.prql

@@ -1,7 +1,7 @@
 ---
 source: book/tests/snapshot.rs
 expression: "prql target:sql.mssql\n\nfrom employees\nsort age\ntake 10\n"
-input_file: book/tests/prql/queries/dialect-and-version-1.prql
+input_file: book/tests/prql/queries/header-1.prql
 ---
 SELECT
   TOP (10) *

book/tests/prql/queries/dialect-and-version-1.prql renamed to book/tests/prql/queries/header-1.prql

@@ -1,7 +1,7 @@
 ---
 source: book/tests/snapshot.rs
 expression: "prql version:\"0.3\"\n\nfrom employees\n"
-input_file: book/tests/prql/queries/dialect-and-version-2.prql
+input_file: book/tests/prql/queries/header-2.prql
 ---
 SELECT
   *

book/tests/prql/queries/dialect-and-version-2.prql renamed to book/tests/prql/queries/header-2.prql

@@ -1,7 +1,7 @@
 ---
 source: book/tests/snapshot.rs
 expression: prql_to_pl(&prql).and_then(pl_to_prql).unwrap()
-input_file: book/tests/prql/queries/dialect-and-version-0.prql
+input_file: book/tests/prql/queries/header-0.prql
 ---
 prql target:sql.postgres
 

book/tests/snapshots/snapshot__@queries__dialect-and-version-0.prql.snap renamed to book/tests/snapshots/snapshot__@queries__header-0.prql.snap

@@ -1,7 +1,7 @@
 ---
 source: book/tests/snapshot.rs
 expression: prql_to_pl(&prql).and_then(pl_to_prql).unwrap()
-input_file: book/tests/prql/queries/dialect-and-version-1.prql
+input_file: book/tests/prql/queries/header-1.prql
 ---
 prql target:sql.mssql
 

book/tests/snapshots/snapshot__@queries__dialect-and-version-1.prql.snap renamed to book/tests/snapshots/snapshot__@queries__header-1.prql.snap

@@ -1,7 +1,7 @@
 ---
 source: book/tests/snapshot.rs
 expression: prql_to_pl(&prql).and_then(pl_to_prql).unwrap()
-input_file: book/tests/prql/queries/dialect-and-version-2.prql
+input_file: book/tests/prql/queries/header-2.prql
 ---
 prql version:^0.4