ci(pr-template): Add PR template for automated dependency updates

[aRustyDev]

Summary

Adds a dedicated PR template for automated dependency update PRs from tools like Dependabot, Renovate, or manual dependency bumps.

Template Type

• PR template (.github/PULL_REQUEST_TEMPLATE/)
• Issue template (.github/ISSUE_TEMPLATE/)
• Mustache template
• Other template type:

Templates Affected

File	Action	Purpose
.github/PULL_REQUEST_TEMPLATE/dependency-update.md	Added	PR template for automated dependency updates

Related Issues

Checklist

General

• Template follows repository naming conventions
• Template includes clear placeholder text/comments for users
• Template is placed in the correct directory

For PR/Issue Templates

• Template includes all required sections
• Checkboxes and options are relevant to the template's purpose
• Labels are correctly referenced (if applicable)

For Mustache/Code Templates

• N/A

Template Preview

Key sections include:

• Update Summary - Table with tool name, update type (major/minor/patch), package manager
• Dependencies Updated - Table for package details with version changes and changelog links
• Risk Assessment - Checkboxes for major/minor/patch/security classification
• Security Notes - Table for CVE details if security-related
• Compatibility Checklist - Breaking changes, peer dependencies, lock file, version constraints
• Testing - CI, unit tests, integration tests, local build verification
• Auto-Merge Eligibility - Criteria for safe auto-merge assessment
• Related PRs - Links to batch dependency updates

Testing

Template designed to complement automated tooling (Dependabot, Renovate) while providing structure for manual review when needed.

Additional Context

This template expands the PR template suite:

• mcp-server-default.md - Default for MCP server changes
• wiki-update.md - For Wiki documentation updates
• templates.md - For contributing new templates
• mcp-onboarding.md - For onboarding new MCP Server repos
• dependency-update.md - For automated dependency updates (this PR)