[Cleanup] Remove DEI badging functionality

[MoralCode]

Note

This PR was ported from augurlabs/augur#3539 filed by @shlokgilda because the contribution was deemed to still be useful.

Summary

• Removes DEI badging routes (/dei/repo/add, /dei/report) and related API endpoints
• Removes BadgingDEI model and dei_badging table from the database
• Removes the dei-badging-report.j2 template
• Adds Alembic migration (revision 39) to drop the dei_badging table
• Cleans up schema SQL and OpenAPI spec

This PR fixes #141

Notes for Reviewers

This is a draft PR - there are a couple other PRs with migrations that need to be merged first before this one can proceed.

Breaking Change

This is a breaking change for any deployments using DEI badging:

• The dei_badging table will be dropped with all existing data
• No migration path for existing data (intentional per maintainer discussion - feature was used for a one-off event by few instances)
• Should be documented in release notes

Migration Notes

• The downgrade() function recreates the table structure but relies on PostgreSQL's implicit sequence creation rather than explicitly recreating dei_badging_id_seq
• Sequence cleanup on upgrade is handled automatically by PostgreSQL when dropping the table (sequence is owned by the column)

Signed commits

• Yes, I signed my commits.

AI Disclosure: This PR draft was generated using Claude Code.

[MoralCode]

• Contains a DB migration that needs to be renumbered

clean for naming, this PR is just deletions and clearing out stuff