feat(P1-002): add offline JSONL import via import_messages MCP tool

- implement `import_messages` MCP tool parsing manifest + PUT/DEL JSONL
- atomic store replacement under lock with overwrite/reject conflict policies
- add `include_deleted` to read_messages export view for full round-trip
- register new tool in MCP registry and update protocol test expectations
- update docs/development-plan.md and docs/implementation-status.md

Debug/Release/ASan 15/15 CTest pass

1 files changed, 19 insertions, 2 deletions

diff --git a/src/mcp/tools/read_messages.c b/src/mcp/tools/read_messages.c
index 079e6eb..647e6f3 100644
--- a/src/mcp/tools/read_messages.c
+++ b/src/mcp/tools/read_messages.c
@@ -734,6 +734,8 @@ call_export_view(tiny_mcp_tools_context_t *context, const mcpc_tool_t *tool, mcp
   char *session = tiny_mcp_tool_get_string(tool, "session_id", TINY_SESSION_ID_MAX);
   char *cursor = tiny_mcp_tool_get_string(tool, "cursor", CURSOR_TEXT_MAX);
   int32_t limit = 500;
+  char *include_deleted_text = tiny_mcp_tool_get_string(tool, "include_deleted", 8);
+  bool include_deleted = include_deleted_text && strcmp(include_deleted_text, "true") == 0;
   bool valid;
   size_t index = simple_cursor(cursor, &valid), emitted = 0, start_index;
   tiny_json_buffer_t json, lines;
@@ -759,13 +761,22 @@ call_export_view(tiny_mcp_tools_context_t *context, const mcpc_tool_t *tool, mcp
       const tiny_store_entry_t *entry = tiny_store_entry(context->store, index);
       tiny_json_buffer_t item;
       size_t line_overhead;
-      if (!entry || entry->deleted
+      if (!entry || (entry->deleted && !include_deleted)
           || (session && session[0] && strcmp(session, entry->message.session_id) != 0))
         {
           continue;
         }
       tiny_json_init(&item);
-      tiny_mcp_tool_append_message(&item, &entry->message);
+      if (entry->deleted)
+        {
+          tiny_json_raw(&item, "{\"type\":\"DEL\",\"message_id\":");
+          tiny_json_string(&item, entry->message.message_id);
+          tiny_json_raw(&item, "}");
+        }
+      else
+        {
+          tiny_mcp_tool_append_message(&item, &entry->message);
+        }
       line_overhead = item.length + 1;
       if (item.failed || outer_size + lines.length + line_overhead + 2 > READ_RESPONSE_BUDGET)
         {
@@ -1011,5 +1022,11 @@ tiny_mcp_register_read_messages(mcpc_server_t *server)
              "omit for the first page.",
              MCPC_U8STR,
              false)
+         && tiny_mcp_tool_add_property(tool,
+                                       "include_deleted",
+                                       "When true, export view includes deleted records as DEL "
+                                       "lines; other views ignore this option.",
+                                       MCPC_U8STR,
+                                       false)
          && mcpc_server_add_tool(server, tool) == MCPC_EC_0;
 }