feat(memory): data migration tool — convert jcode JSON MemoryGraph to mempalace [phase-5]

[quangdang46]

Problem

jcode stores memories as MemoryGraph in JSON files (~/.jcode/memory/global.json, ~/.jcode/memory/projects/<hash>.json). Each MemoryEntry has inline embeddings, tags, edges, clusters, and metadata. These must be migrated into mempalace's Drawer + KG format.

Scope

Files: New crates/jcode-mempalace-adapter/src/migrate.rs

1. Migration function:

   pub async fn migrate_to_mempalace(
       jcode_memory_dir: &Path,    // ~/.jcode/memory/
       palace_path: &Path,          // target mempalace path
       dry_run: bool,
   ) -> anyhow::Result<MigrationReport>

2. Migration steps (for each JSON file):

   a. Memories → Drawers: For each MemoryEntry in the graph:

   • Create Drawer with mapped DrawerKind, content, tags, trust, confidence, strength
   • Map created_at/updated_at timestamps
   • Preserve embedding in Drawer (via metadata or direct vector store insert)
   • Call MemoryProvider::add_drawer()

   b. Tags → KG entities + HasTag edges: For each TagEntry:

   • Create KG entity with name = tag name
   • For each memory with that tag, create HasTag triple

   c. Edges → KG triples with typed edge kinds: For each Edge:

   • RelatesTo { weight } → KG triple with MemoryEdgeKind::RelatesTo
   • Supersedes → MemoryEdgeKind::Supersedes
   • Contradicts → MemoryEdgeKind::Contradicts
   • DerivedFrom → MemoryEdgeKind::DerivedFrom
   • InCluster → MemoryEdgeKind::InCluster

   d. Clusters → KG clusters: For each ClusterEntry:

   • Create cluster with centroid, member_count
   • Create InCluster edges to members

   e. Legacy MemoryStore (v1) format: Also handle the old MemoryStore format (flat Vec) that gets auto-migrated to MemoryGraph.

3. Safety:

   • Write .bak file before any changes
   • Dry-run mode: report counts without writing
   • Idempotent: running twice produces same result

4. MigrationReport:

   pub struct MigrationReport {
       pub memories_migrated: usize,
       pub tags_migrated: usize,
       pub edges_migrated: usize,
       pub clusters_migrated: usize,
       pub errors: Vec<String>,
       pub duration: std::time::Duration,
   }

5. CLI command: jcode memory migrate --to-mempalace [--dry-run] [--palace-path PATH]

Acceptance Criteria

• A jcode MemoryGraph with N memories, M tags, E edges, C clusters is fully migrated
• All data round-trips: memories, tags, edges, clusters, embeddings
• Embeddings are preserved in mempalace vector store
• .bak files created before migration
• Dry-run mode reports accurate counts without modifying anything
• Idempotent: second run is a no-op
• Legacy v1 MemoryStore format also handled
• CLI command works end-to-end

Dependencies

• jcode --mode rpc: strict LF-delimited JSONL protocol for IDE / external integrations #12 (MempalaceAdapter must exist for the migration to call Palace APIs)

Reference

jcode MemoryGraph JSON: ~/.jcode/memory/global.json, ~/.jcode/memory/projects/<hash>.json
jcode MemoryGraph struct: crates/jcode-memory-types/src/graph.rs lines 231-256
jcode MemoryEntry: crates/jcode-memory-types/src/lib.rs lines 233-266
jcode legacy migration: crates/jcode-base/src/memory.rs lines 1529-1577

[quangdang46]

Closed — implemented in PR #364 (merged). Data migration tool in with dry-run mode and MigrationReport.