feat: add MongoDB data importer tool and update README

tools/importer/README.md

@@ -0,0 +1,48 @@
+# MCP Registry Importer Tool
+
+This command-line tool imports server data from a JSON file into a MongoDB database for the Model Context Protocol Registry.
+
+## Usage
+
+```bash
+go run main.go [options]
+```
+
+### Options
+
+- `-uri string`: MongoDB connection URI (default "mongodb://localhost:27017")
+- `-db string`: MongoDB database name (default "mcp_registry")
+- `-collection string`: MongoDB collection name (default "servers")
+- `-seed string`: Path to seed.json file (default: looks for data/seed.json relative to current directory)
+- `-drop`: Drop collection before importing (default false)
+
+### Examples
+
+Import data using default settings:
+```bash
+go run main.go
+```
+
+Import data into a specific MongoDB instance:
+```bash
+go run main.go -uri mongodb://username:password@example.com:27017 -db registry
+```
+
+Import data from a specific seed file and replace all existing data:
+```bash
+go run main.go -seed /path/to/custom-seed.json -drop
+```
+
+## Building
+
+To build the tool as an executable:
+
+```bash
+go build -o registry-importer
+```
+
+Then you can run it directly:
+
+```bash
+./registry-importer [options]
+```