refactor(validations): split lib/validations.ts into a barrel'd folder (slice 1)

1141-line lib/validations.ts → lib/validations/<feature>.ts + primitives.ts +
an index.ts barrel. '@/lib/validations' now resolves to the barrel, so all 40
importers are untouched. Every one of the 143 exports is preserved verbatim
(verified by symbol-diff); schemas moved unchanged. tsc 0, 635 tests green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/validations/onboarding.ts

@@ -0,0 +1,26 @@
+import { z } from 'zod'
+
+export const onboardingStepTypeSchema = z.enum(['welcome', 'code_of_conduct', 'profile', 'payment', 'content', 'form'])
+
+export const createOnboardingStepSchema = z.object({
+  step_type: onboardingStepTypeSchema,
+  title: z.string().min(1, 'Title is required').max(200),
+  body: z.string().max(50000).optional().nullable(),
+  config: z.record(z.unknown()).optional(),
+  is_enabled: z.boolean().optional(),
+  is_required: z.boolean().optional(),
+  sort_order: z.number().int().min(0).max(100000).optional(),
+})
+
+export const updateOnboardingStepSchema = z.object({
+  title: z.string().min(1).max(200).optional(),
+  body: z.string().max(50000).optional().nullable(),
+  config: z.record(z.unknown()).optional(),
+  is_enabled: z.boolean().optional(),
+  is_required: z.boolean().optional(),
+  sort_order: z.number().int().min(0).max(100000).optional(),
+})
+
+export const discloseAffiliationsSchema = z.object({
+  affiliations: z.array(z.string().min(1).max(200)).max(50).default([]),
+})