Simplify seed data configuration by removing command line flags and renaming environment variable (#175)

This PR simplifies the seed data import configuration based on
maintainer feedback by removing command line flags and using a clearer
environment variable name.

## Key Changes

### Configuration Simplification
- **Renamed**: `MCP_REGISTRY_SEED_FILE_PATH` → `MCP_REGISTRY_SEED_FROM`
- **Removed**: `--seed-file-path` command line flag to eliminate
configuration complexity

### Improved User Experience
Users now configure seed data import using a single, clear environment
variable:

```bash
# Before (multiple ways to configure)
MCP_REGISTRY_SEED_FILE_PATH=data/seed.json ./registry
./registry --seed-file-path=data/seed.json

# After (simplified single method)
MCP_REGISTRY_SEED_FROM=data/seed.json ./registry
```

### Registry Composability
The composability workflow is now simplified while maintaining all
functionality:

```bash
# Start first registry with seed data
MCP_REGISTRY_SEED_FROM=data/seed.json ./registry

# Start second registry importing from first via pagination
MCP_REGISTRY_SEED_FROM=http://localhost:8080 ./registry
```

## Technical Implementation
- Maintains full backward compatibility for import functionality
- All existing seed data sources continue to work (local files, HTTP
URLs, registry URLs)
- Automatic pagination through `/v0/servers` endpoint remains unchanged
- Configurable delays between requests preserved

## Benefits
- **Reduced complexity**: Single configuration method instead of
multiple
- **Clearer naming**: `SEED_FROM` better describes the source of seed
data
- **Easier maintenance**: Fewer configuration paths to test and document
- **Consistent patterns**: Aligns with other environment-variable-only
configuration

All existing functionality is preserved while providing a cleaner, more
maintainable configuration interface.

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Co-authored-by: toby <83556+toby@users.noreply.github.com>

README.md

@@ -27,12 +27,14 @@ The MCP Registry service provides a centralized repository for MCP server entrie
 - MongoDB and in-memory database support
 - Comprehensive API documentation
 - Pagination support for listing registry entries
+- Seed data export/import composability with HTTP support
+- Registry instance data sharing via HTTP endpoints
 
 ## Getting Started
 
 ### Prerequisites
 
-- Go 1.23.x (required - check with `go version`)
+- Go 1.24.x (required - check with `go version`)
 - MongoDB
 - Docker (optional, but recommended for development)
 
@@ -413,8 +415,7 @@ The service can be configured using environment variables:
 | `MCP_REGISTRY_GITHUB_CLIENT_ID`      | GitHub App Client ID |  |
 | `MCP_REGISTRY_GITHUB_CLIENT_SECRET`  | GitHub App Client Secret |  |
 | `MCP_REGISTRY_LOG_LEVEL`             | Log level | `info` |
-| `MCP_REGISTRY_SEED_FILE_PATH`        | Path to import seed file | `data/seed.json` |
-| `MCP_REGISTRY_SEED_IMPORT`           | Import `seed.json` on first run | `true` |
+| `MCP_REGISTRY_SEED_FROM`             | Path or URL to import seed data (supports local files and HTTP URLs) | `data/seed.json` |
 | `MCP_REGISTRY_SERVER_ADDRESS`        | Listen address for the server | `:8080` |
 
 ## Pre-built Docker Images
@@ -435,6 +436,35 @@ docker run -p 8080:8080 ghcr.io/modelcontextprotocol/registry:main-20250806-a1b2
 
 **Configuration:** The Docker images support all environment variables listed in the [Configuration](#configuration) section. For production deployments, you'll need to configure the database connection and other settings via environment variables.
 
+### Import Seed Data
+
+Registry instances can import data from:
+
+**Local files:**
+```bash
+MCP_REGISTRY_SEED_FROM=data/seed.json ./registry
+```
+
+**HTTP endpoints:**
+```bash
+MCP_REGISTRY_SEED_FROM=http://other-registry:8080 ./registry
+```
+
+## Testing
+
+Run the test script to validate API endpoints:
+
+```bash
+./scripts/test_endpoints.sh
+```
+
+You can specify specific endpoints to test:
+
+```bash
+./scripts/test_endpoints.sh --endpoint health
+./scripts/test_endpoints.sh --endpoint servers
+```
+
 ## License
 
 See the [LICENSE](LICENSE) file for details.