refactor(validations): export Zod validation schemas and TypeScript types for suppliers, facilities, routes, activities, and authentication in [validations.ts]

[mspandey]

Problem

Currently, validations.ts implements Zod schemas and TypeScript inference types for payload validation across suppliers, facilities, transport routes, emission activities, and user authentication (signupSchema, loginSchema). Ensuring clean exports and rigorous validation rules is essential for maintaining backend and frontend type safety.

Proposed Solution

Verify and maintain clean ES module exports for all Zod validation schemas and inferred types in validations.ts.

Acceptance Criteria

• Export individual and payload array schemas (supplierSchema, suppliersPayloadSchema, facilitySchema, facilitiesPayloadSchema, routeSchema, routesPayloadSchema, activitySchema, activitiesPayloadSchema, signupSchema, loginSchema) from validations.ts.
• Export corresponding TypeScript input types (SupplierInput, FacilityInput, RouteInput, ActivityInput, SignupInput, LoginInput) using z.infer.
• Ensure coordinate coercions, positive number validations, and strict password complexity regex rules operate correctly.
• Verify that importing validation schemas into API routes passes all test suites successfully.

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