feat: Clean JSONL export/import for memories

[ajianaz]

What

Wire /export and /import endpoints so users can export memories to JSONL and import them back (backup, migration, transfer between namespaces).

Why

No backup/export path = data lock-in. Users need a way to:

• Backup memories before major lifecycle operations
• Migrate between namespaces or instances
• Share memory sets between agents

How

Endpoints

Endpoint	Method	Return
GET /export	?namespace=X&format=jsonl -> JSONL stream	Existing
POST /import	JSONL body -> {imported, skipped, errors}	Existing

Implementation

Layer 0-2: Standard pattern. Export returns streaming text, import sends JSONL body.

Layer 3 — Settings or Tools menu:

• Export:
  • Namespace selector (or "all")
  • [Export to JSONL] -> native file save dialog
  • Progress indicator for large exports
• Import:
  • [Import JSONL] -> native file open dialog
  • Preview: show count, first 5 entries
  • Confirmation: "Import N memories? Duplicates will be skipped."
  • Result: "Imported N, skipped N duplicates, N errors"

Safety

• Import always dedup (skip existing IDs)
• Preview before commit
• Export includes metadata (version, timestamp, namespace)

Testing

• Export creates valid JSONL file
• Import reads JSONL -> creates memories
• Import skips duplicates
• Import shows error count for malformed entries
• Round-trip: export -> import -> same data

Related Issues

• Part of: Phase 2B endpoint gap fill

Checklist

• Layer 0-3 for /export and /import
• File save dialog for export
• File open dialog + preview for import
• Result summary

[ajianaz]

Done — server-native JSONL is now a first-class format in the Settings → Data import/export panel (rides the next PR):

• Export: new JSONL (server) format card → GET /export (with namespace filter); desktop uses the native save dialog, web downloads a .jsonl blob
• Import: .jsonl files are detected, parsed client-side (parseJsonl helper + 5 unit tests), and previewed with entry count, malformed-line count, and the first 5 entries — plus an optional target-namespace override for cross-namespace migration
• Result summary: imported / malformed-skipped counts straight from POST /import
• ToolsView's raw JSONL path (built in feat: Fill UtekeClient gaps — 5 high-priority endpoints (PUT /memory, /room/remember, /import, /export, /context) #216/feat: Room-document linking — add/list/remove docs to rooms #231) remains for power users

Semantics verified live against uteke 0.15.0: new content → imported: 1; exact re-import → silently deduplicated; malformed line → skipped: 1. Round-trip export → import verified in the browser.