Release v0.6.0

[joaoh82]

Bumps every product to v0.6.0 (previously v0.5.1). Minor release covering the SQLR-7 SQL surface addition + INSERT NULL handling cleanup.

Included since v0.5.1

• #95 — feat(sql): IS NULL / IS NOT NULL + typed Option INSERT pipeline (SQLR-7).
  • New SQL surface: WHERE col IS NULL / IS NOT NULL (full-scan; NULLs aren't indexed).
  • Refactors INSERT to carry Vec<Vec<Option<Value>>> end-to-end instead of a stringly-typed "Null" sentinel — fixes panics on INSERT … VALUES (NULL) for INTEGER / REAL / BOOLEAN / VECTOR columns and the silent-"Null"-text storage on TEXT columns.
  • Persistence side: Table::restore_row now accepts NULL for non-text column types so a saved DB containing any NULL outside TEXT reopens cleanly. Without this, the smoke test's reopen failed.
  • SQL UNIQUE allows multiple NULLs (standard three-valued logic).
  • DEFAULT NULL collapses to "no default"; explicit NULL in INSERT is preserved over a column DEFAULT (matches SQLite). Restored the SQLR-2 default_does_not_override_explicit_null test that had to be dropped because of this bug.
  • Docs: removed "not yet supported" notes for IS NULL / IS NOT NULL from README, supported-sql.md, usage.md, roadmap.md.

Test plan

• scripts/bump-version.sh 0.6.0 (12 manifests touched, plus Cargo.lock refresh)
• cargo build --workspace --exclude sqlrite-desktop --exclude sqlrite-python --exclude sqlrite-nodejs clean
• CI green on this PR

What merging triggers

release.yml runs against the merge commit:

1. Tags sqlrite-v0.6.0, sqlrite-ffi-v0.6.0, and umbrella v0.6.0.
2. Publishes the Rust crates (sqlrite-engine, sqlrite-ffi, sqlrite-ask).
3. Publishes the Python (PyPI), Node (npm), and WASM (npm) SDKs.
4. Creates the umbrella v0.6.0 GitHub Release with auto-generated notes.

🤖 Generated with Claude Code