perf(api): add max length constraints to Zod schemas for body fields

Problem

Several Zod schemas used to validate request bodies lack .max() constraints on string and array fields. Even with a body size limit, unbounded schemas allow expensive validation passes on large inputs.

Affected Schemas

Suggested Fix

Add appropriate .max() constraints:

// Example for pricing
z.array(PricingSpecsSchema).max(50)

// Example for SDL
z.string().max(1_000_000) // 1MB max SDL

// Example for bio
z.string().max(500)

// Example for messages
messages: z.array(messageSchema).min(1).max(100)

Files

• apps/api/src/billing/http-schemas/sign-tx.schema.ts
• apps/api/src/pricing/http-schemas/pricing.schema.ts
• apps/api/src/deployment/http-schemas/deployment.schema.ts
• apps/api/src/routers/userRouter.ts

Context

Part of the API event loop performance audit.

Read the schemas in apps/api/src/billing/http-schemas/sign-tx.schema.ts and apps/api/src/deployment/http-schemas/deployment.schema.ts, then inspect the user template fields in apps/api/src/routers/userRouter.ts. Determine suitable maximums for the remaining messages, SDL, certificate, and title fields; done means those request-body fields enforce explicit limits without changing unrelated schemas.