feat: implement export and import commands

- Add export command with JSON file output and size summary
- Add import command with replace/merge strategies and dry-run preview
- Add integration test for export/import round-trip via storage layer
- Update project state documentation

PROJECT_STATE.md

@@ -2,7 +2,7 @@
 
 > **Purpose**: Enable seamless continuation of development by any agent/LLM across sessions
 > 
-> **Last Updated**: 2024-06-23 (Session 7)
+> **Last Updated**: 2024-06-23 (Session 8)
 > **Current Status**: Implementation In Progress - Tasks 1-8 Complete
 > **Phase**: MVP Development (Phase 1)
 
@@ -33,10 +33,9 @@
 ✅ **Bug Fix**: Fixed deadlock in JSON storage (RLock within Lock)
 
 ### What Needs to Happen Next
-🔄 **Task 11**: Export/Import commands
-🔄 Key management commands
-🔄 Build and test core features
-🔄 Prepare MVP release
+🔄 **Task 12**: Build and Testing (Makefile, integration tests)
+🔄 **Task 13**: Documentation (README, usage docs)
+🔄 **Task 14**: Final testing and release prep
 
 ---
 
@@ -53,12 +52,12 @@
 | **Errors** | ✅ 100% | AppError + ConnectionError + SSH error handler |
 | **SSH Client** | ✅ 100% | Password + key auth, Execute, Connect/Close |
 | **CLI Framework** | ✅ 100% | Cobra root, version, completion commands |
-| **CLI Commands** | 🟡 60% | add + list + connect + edit + delete commands done |
+| **CLI Commands** | 🟡 70% | add + list + connect + edit + delete + export + import done |
 | **TUI** | 🟡 40% | Basic TUI with host list navigation |
-| **Testing** | 🟡 50% | Error + SSH + add + list + connect + edit + delete + TUI tests passing |
+| **Testing** | 🟡 55% | Error + SSH + add + list + connect + edit + delete + TUI + export/import tests passing |
 | **Documentation** | 🔲 0% | Usage guides and API docs |
 
-### Overall Progress: **~70% Complete** (Tasks 1-10 done)
+### Overall Progress: **~75% Complete** (Tasks 1-11 done)
 
 ---
 
@@ -169,7 +168,16 @@
   - `pkg/tui/tui_test.go` — Tests for TUI initialization and host loading
   - `cmd/hostkeeper/tui.go` — CLI `tui` command
 
-#### 🔲 Task 11-14: Remaining Tasks
+#### ✅ Task 11: Export/Import Commands
+- **Status**: ✅ Completed
+- **Priority**: HIGH
+- **Deliverables**: Export/import hosts, keys, snippets for backup/transfer
+- **Files Created**:
+  - `cmd/hostkeeper/export.go` — Export command with JSON format (default) and include-keys flag
+  - `cmd/hostkeeper/import.go` — Import command with replace/merge strategies and dry-run preview
+  - `test/storage/export_import_test.go` — Integration test for export/import round-trip
+
+#### 🔲 Task 12-14: Remaining Tasks
 - **Status**: Not Started
 - **Details**: See `docs/plans/2024-06-22-hostkeeper-implementation.md`