endtoend: pin sqlite query text with multi-byte UTF-8 comments (#4568)

The ANTLR-based sqlite parser mixed rune-counted and byte-counted
offsets when slicing query text out of the source file, so a multi-byte
character in a comment silently truncated the generated query string
and leaked fragments of neighboring statements into it. The meyer
parser tracks byte offsets throughout, which fixed this; this case
keeps it fixed.

Covers the three reported shapes: an em dash in a comment directly
above the annotation, a standalone comment between two queries, and
CJK comments.

Fixes #4523
Fixes #4235
Fixes #4372


Claude-Session: https://claude.ai/code/session_017bkCyEYanANjRyamjUF8ZP

Co-authored-by: Claude <noreply@anthropic.com>

Author: kyleconroy

internal/endtoend/testdata/multibyte_comment/sqlite/go/db.go

@@ -0,0 +1,20 @@
+-- Multi-byte UTF-8 in comments must not shift the byte offsets used to slice
+-- query text out of the source file (#4523, #4235, #4372).
+
+-- name: ListItems :many
+-- an em dash right here — must not truncate the ORDER BY below
+SELECT id, name, cap_read
+FROM items WHERE cap_read = 'anonymous' ORDER BY name;
+
+-- section — divider between queries
+
+-- name: UpdateItem :exec
+UPDATE items SET name = ? WHERE id = ?;
+
+-- name: CreateItem :exec
+-- 当新建条目时，需要写入名称和权限
+INSERT INTO items (name, cap_read)
+VALUES (?, ?);
+
+-- name: DeleteItem :one
+DELETE FROM items WHERE id = ? RETURNING id, name, cap_read;

internal/endtoend/testdata/multibyte_comment/sqlite/go/models.go

@@ -0,0 +1,5 @@
+CREATE TABLE items (
+  id       INTEGER PRIMARY KEY,
+  name     TEXT NOT NULL,
+  cap_read TEXT NOT NULL
+);

internal/endtoend/testdata/multibyte_comment/sqlite/go/query.sql.go

@@ -0,0 +1,12 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "path": "go",
+      "engine": "sqlite",
+      "name": "querytest",
+      "schema": "schema.sql",
+      "queries": "query.sql"
+    }
+  ]
+}