Release v0.2.0

Phase 5a polish drop.

New features

• Re-convert (replace): right-click → Re-convert with Docling (replace) deletes the existing .md sibling and re-runs the conversion. Only shown when there's already an .md to replace.
• YAML frontmatter built from Zotero parent metadata (title, authors, year, doi, url, zotero_key, citation_key) prepended to every .md output. Toggleable.
• Export-to-folder: optional secondary sink. Set an absolute directory in prefs and every converted .md is also written there as {citationKey || zoteroKey}.md.
• Concurrency control (`maxConcurrency`, default 1): convert multiple PDFs in parallel within one batch. Pairs with the async endpoint + a docling-serve started with `--workers ≥ 2`.
• OS-level notifications when a batch finishes if Zotero isn't focused.
• Reset to Defaults button in the prefs pane to wipe all plugin prefs back to built-in defaults.
• Per-parent status tags (`docling/done`, `docling/incomplete`, `docling/error`) so you can filter your library by conversion status.

Fixes

• Fluent parser error on the Export-folder help string that previously caused the locale key to be silently dropped.

Internal

• `ConcurrencyLimiter` semaphore utility.
• DB-write lock to serialize attachment creation against the Zotero SQLite store.
• Blur-aware managed progress window that stops updating cleanly when Zotero is hidden.