Artifact tool labels that are too long are trimmed or cut instead of rejected

What

When Claude creates an artifact, it gives it a short label (a name). This release changes what happens when that label is too long.

• The label is now cleaned up first: Windows-style line endings (CRLF) become plain line endings (LF), and extra space at the ends is removed.
• If it is still too long, it is cut to the limit, and a note about the change is attached to the tool's result.
• The "label is a short name" hint, which tells Claude to move longer text into the page content, now fires when schema validation (the check of the tool's input format) reports the label as too big.
• The maximum length now comes from a constant. Before, the check was a fixed "more than 60 characters".

Why

Fewer artifact tool calls should fail just because Claude wrote a long label. Because the limit is no longer written as a fixed 60, the actual maximum may be different in this build.