docs(readme): add Discord community badge

[benvinegar]

Summary

• add a Discord community badge beside the existing README badges
• link the badge to the existing Modem Discord invite
• include an empty Changeset because this is documentation-only maintenance

Validation

• git diff --check
• verified the Shields.io badge returns HTTP 200
• verified the Discord invite returns HTTP 200

Platforms

Not platform-specific; no full test suite was run for this README-only change.

This PR description was generated by Pi using gpt-5.6-sol

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1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
hunk-web	Ignored	Preview	Aug 30, 2026 1:07am

[greptile-apps]

Greptile Summary

This documentation-only PR adds a Discord community badge to the README and records the maintenance change with an empty Changeset.

• Adds a Shields.io Discord badge linked to the existing Modem Discord invite.
• Adds a repository-standard empty Changeset.

Confidence Score: 5/5

The PR appears safe to merge with no actionable issues identified.

The badge follows existing README conventions, reuses the established Discord invite, and the empty Changeset matches the repository's documented format.

Important Files Changed

Filename	Overview
README.md	Adds a Discord community badge consistent with the existing badge markup and established invite URL.
.changeset/add-discord-readme-badge.md	Adds a valid empty Changeset consistent with the repository's documented maintenance-change convention.

_{Reviews (1): Last reviewed commit: "docs(readme): add Discord community badg..." | Re-trigger Greptile}