Upgrade gqlgen from v0.17.70 to v0.17.88

[BrewingCoder]

Problem

Running gqlgen v0.17.70, latest is v0.17.88 (18 versions behind). During billing removal work, gqlgen was crashing silently (exit 1, no output) which may have contributed to a page fault that corrupted files mid-write.

Known issues with older gqlgen:

• Silent failures when Go packages have compile errors
• Memory pressure during AST parsing of large codebases
• bufio: buffer full errors from corrupted build cache

Action

• Bump github.com/99designs/gqlgen from v0.17.70 to v0.17.88
• Run go mod tidy
• Regenerate all GraphQL code (make private-gen / make public-gen)
• Verify build + tests pass

Test Plan

• go build ./...
• go test ./... (short mode)
• gqlgen generates without errors
• CI green

🤖 Generated with Claude Code

[github-actions]

AI Triage: Upgrade gqlgen dependency from v0.17.70 to v0.17.88 to fix silent failures and memory issues affecting GraphQL code generation.

Labels applied: area:backend, tech-debt, priority:high, component:graphql