Deployment: Dockerfile and Smithery config (#2)

* Add Dockerfile

* Add Smithery configuration

* Update README

---------

Co-authored-by: smithery-ai[bot] <194235850+smithery-ai[bot]@users.noreply.github.com>

smithery.yaml

@@ -0,0 +1,16 @@
+# Smithery configuration file: https://smithery.ai/docs/config#smitheryyaml
+
+startCommand:
+  type: stdio
+  configSchema:
+    # JSON Schema defining the configuration options for the MCP.
+    type: object
+    required: []
+    properties:
+      excelFilesPath:
+        type: string
+        description: Directory where Excel files will be stored.
+  commandFunction:
+    # A function that produces the CLI command to start the MCP on stdio.
+    |-
+    config => ({ command: 'uv', args: ['run', 'excel-mcp-server'], env: { EXCEL_FILES_PATH: config.excelFilesPath || './excel_files' } })