feat(mcp): add offset/limit params and show file metadata in declarations

- Add offset and limit parameters to get_file tool schema
- Default limit is 250 lines, offset is 0
- Show "Showing lines X-Y of Z total" header when range is applied
- Update handleGetOption to use GetDeclarationsWithMetadata
- Display file size metadata (bytes, lines) in declarations output

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/mcp/server.go

@@ -28,7 +28,7 @@ type ServerConfig struct {
 func DefaultNixOSConfig() ServerConfig {
 	return ServerConfig{
 		Name:           "nixos-options",
-		Version:        "0.1.1",
+		Version:        "0.1.2",
 		DefaultChannel: "nixos-stable",
 		SourceName:     "nixpkgs",
 		Instructions: `NixOS Options MCP Server - Search and query NixOS configuration options.
@@ -47,7 +47,7 @@ This ensures option documentation matches the nixpkgs version the project actual
 func DefaultHomeManagerConfig() ServerConfig {
 	return ServerConfig{
 		Name:           "hm-options",
-		Version:        "0.1.1",
+		Version:        "0.1.2",
 		DefaultChannel: "hm-stable",
 		SourceName:     "home-manager",
 		Instructions: `Home Manager Options MCP Server - Search and query Home Manager configuration options.
@@ -291,6 +291,16 @@ func (s *Server) getToolDefinitions() []Tool {
 						Type:        "string",
 						Description: "Git hash or channel name. Uses default if not specified.",
 					},
+					"offset": {
+						Type:        "integer",
+						Description: "Line offset (0-based). Default: 0",
+						Default:     0,
+					},
+					"limit": {
+						Type:        "integer",
+						Description: "Maximum lines to return. Default: 250, use 0 for all lines",
+						Default:     250,
+					},
 				},
 				Required: []string{"path"},
 			},