Panic: assertion failed: start.raw <= end.raw on a WITH followed by a blank line and an indented CTE

[edjubert]

Describe the bug

check panics on a valid query when a WITH keyword is followed by a blank line and
the CTE definition is indented. The panic aborts the whole run, so a single file of this
shape stops check from finishing over a directory.

This is the same assertion as the already-closed #303, but a different trigger, and it
reproduces on 0.25.7.

To Reproduce

repro.sql (4 lines, note the leading whitespace on line 3):

WITH

 x AS (SELECT 1 AS a)
SELECT x.a FROM x;

$ postgres-language-server check repro.sql
Encountered an unexpected error

Source Location: crates/pgls_text_size/src/range.rs:50:9
Thread Name: main
Message: assertion failed: start.raw <= end.raw

Both conditions are required. Removing either one avoids the panic:

Input	Result
WITH + blank line + indented CTE (tab, 1 space or 4 spaces)	panic
WITH + blank line + unindented CTE	no panic
WITH + no blank line + indented CTE	no panic

Expected behavior

No panic. A diagnostic is fine, a crash is not, especially since it terminates the run
and leaves the remaining files unchecked.

System information

• postgres-language-server 0.25.7
• macOS (aarch64), release binary postgres-language-server_aarch64-apple-darwin