Update README.md with BaseStation PDF form fill server

[benhuang21828]

Add PDF form fill (BaseStation) to Community Servers

Description

Server Details

• Server:
• Changes to:

Motivation and Context

How Has This Been Tested?

Breaking Changes

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Protocol Documentation
• My changes follows MCP security best practices
• I have updated the server's README accordingly
• I have tested this with an LLM client
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have documented all environment variables and configuration options

Additional context

[benhuang21828]

Add PDF form fill (BaseStation) to Community Servers

What: Adds “PDF form fill (BaseStation)” to the Community Servers list.
Repo: https://github.com/Base-Station-Inc/pdfkit-mcp
Tool: basestation.create_autofill_job
Transports: stdio (npx), streamable-http
Auth: requires BASESTATION_API_KEY
Scope: focuses on PDF form filling