blobl v0.4.1 — editor and formatting improvements

Bloblang editor and formatter improvements:

• Signature help, hierarchical document symbols, and folding ranges.
• Workspace references follow the same discovery rules as rename, including imports, YAML and live buffers.
• YAML formatting and quick fixes preserve indentation, scalar headers, anchors, tags, comments and line endings.
• Lint suppression comments stay attached when formatting wraps a statement.
• Document generations, a coalescing diagnostic sender, cancellation and parser disposal prevent stale results and close/reopen races.
• Preview results are shared through a bounded cache; inlay hints respect requested ranges.
• Samples are limited to regular files up to 4 MiB; generated storage directories are excluded from recursive CLI scans.

The public binary remains blobl. Legacy server binaries and extension archive names remain compatible.