Remove PromoCode field and hardcoded PromoCodes map

[BrewingCoder]

Parent: #25 — Remove all SaaS billing code

What to Remove

Workspace struct

Field	Line
PromoCode	307 (*string)

Resolver code

• PromoCode struct definition — private-graph/graph/resolver.go:103-107
• PromoCodes map with hardcoded promo codes — private-graph/graph/resolver.go:108-125
  • WEBDEVSIMPLIFIED, CATCHMYERRORS, SIMPLIFIEDHIGHLIGHT, USEGOLANG (Highlight.io marketing)

Callers

File	Line	Usage
private-graph/graph/schema.resolvers.go	425	PromoCode param in CreateWorkspace
private-graph/graph/schema.resolvers.go	522	Lookup: PromoCodes[strings.ToUpper(*promoCode)]
private-graph/graph/schema.resolvers.go	539	Assignment to workspace
private-graph/graph/generated/generated.go	97852	GraphQL field resolver
private-graph/graph/model/models_gen.go	94	Generated GraphQL model field

Migration Required

• Drop promo_code from workspaces table

Test Plan

• Remove field from Workspace
• Remove PromoCode struct and PromoCodes map from resolver
• Remove promo code logic from CreateWorkspace
• Update GraphQL schema
• Regenerate: make private-gen + yarn codegen
• Add column-drop migration
• Verify build + tests

🤖 Generated with Claude Code

[github-actions]

AI Triage: Remove PromoCode field from Workspace struct and hardcoded PromoCodes map as part of SaaS billing code cleanup.

Labels applied: area:backend, tech-debt, billing-removal, priority:medium, component:graphql, component:database