Plugin: importer (Obsidian / Notion / Logseq) (#73)

[thetechjon]

Summary

Closes #73. Lands public/plugins/noteser-importer as the first end-to-end consumer of the v1.2 plugin API, exercising the fullscreenView surface, ctx.fs.openDirectory, ctx.requestFileOpen, ctx.vault.write.createNote, and ctx.onVNodeEvent together.

The plugin renders a fullscreen view with a source-format radio (Obsidian vault folder / Notion ZIP export / Logseq export folder), opens the matching native picker, walks the source, and creates notes through vault.write.createNote. Conflict resolution lives in the host: createNote already auto-suffixes (imported) on title collisions and the response carries conflictResolved, which the plugin tallies. Logseq ((block-id)) references degrade to a literal blockquote (> note from Logseq import: block ref <id>) and bump a lossy counter shown in the summary.

Why a plugin (not core)

The v1.2 plan (docs/plugins-v1.2-plan.md §13) calls out the importer specifically as a v1.2 use case. The plugin surface exists exactly so that drop-in format support like this does not have to live in core. Per Jon's rule "plugin where possible" — this PR moves importer logic out of core entirely (issue #73 originally proposed src/utils/import.ts).

Library choice — fflate

Notion exports arrive as a single .zip. Options considered:

• jszip (already a noteser core dep): ~96 KB minified, ~28 KB gz, but it is bundled into the core app. Shipping it via the plugin URL would mean a second copy at the user's plugin host.
• fflate browser ESM: 91 KB raw, ~22 KB gz, MIT-licensed. Exposes unzipSync as a named export. Shipped vendored as public/plugins/noteser-importer/fflate.module.js, matching the noteser-pdf-export/jspdf.es.min.js pattern.

22 KB gz is heavier than the ideal ~10 KB gz target because fflate ships the full compress + decompress surface; the plugin only calls unzipSync. A future v0.2 could swap to the UMD-min build (~12 KB gz) or a hand-trimmed inflate-only fork if size pressure shows up. For v0.1 the standard ESM keeps the diff reviewable.

Lossy conversions documented

• Obsidian — verbatim. Wikilinks ([[Note]]), frontmatter, and #tags survive.
• Notion — 32-character hex Notion ids stripped from filenames AND folder segments. Intra-vault .md links ([Label](Page%20name%20abc...md)) rewrite to [[Label]]. External https:// links and .csv (database) links pass through untouched.
• Logseq — wikilinks pass through. ((block-id)) references degrade to > note from Logseq import: block ref <id> (the cross-page block index is not portable) and the count surfaces in the final summary.

Test plan

• npm run lint clean
• npx tsc --noEmit zero errors
• npm test -- --ci green (2578 passing, 17 skipped, including the new 14 importerPlugin tests)
• Manual smoke: install plugin via "Add plugin from URL" pointing at /plugins/noteser-importer/manifest.json, run "Import notes from..." from the command palette, pick a small Obsidian folder, confirm notes land in the sidebar with folder structure preserved

Files touched

docs/plugins-v1.2-impl-notes.md                                     (appended)
public/plugins/noteser-importer/manifest.json                       (new)
public/plugins/noteser-importer/main.js                             (new)
public/plugins/noteser-importer/parsers.js                          (new)
public/plugins/noteser-importer/fflate.module.js                    (new — vendored)
src/plugins/__tests__/importerPlugin.test.ts                        (new)

Co-Authored-By: Claude Opus 4.7