feat: default new Codex agents to the qualified Paperclip Runner

Resolve creation intent across onboarding, hires, imports, and the UI. Preserve existing execution and qualify automatic defaults for shipped Linux x64 artifacts.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

packages/shared/src/validators/agent.ts

@@ -94,6 +94,7 @@ export const createAgentSchema = z.object({
   capabilities: z.string().optional().nullable(),
   desiredSkills: z.array(agentDesiredSkillSelectionSchema).optional(),
   adapterType: agentAdapterTypeSchema,
+  runner: z.enum(["auto", "paperclip", "legacy"]).optional(),
   adapterConfig: adapterConfigSchema.optional().default({}),
   instructionsBundle: createAgentInstructionsBundleSchema.optional(),
   runtimeConfig: agentRuntimeConfigSchema.optional().default({}),
@@ -122,6 +123,7 @@ export type CreateAgent = z.infer<typeof createAgentSchema>;
 
 export const builtInAgentProvisionSchema = z.object({
   adapterType: agentAdapterTypeSchema.optional(),
+  runner: z.enum(["auto", "paperclip", "legacy"]).optional(),
   adapterConfig: adapterConfigSchema.optional(),
   budgetMonthlyCents: z.number().int().nonnegative().optional(),
 }).strict();
@@ -257,6 +259,7 @@ export const resetAgentSessionSchema = z.object({
 export type ResetAgentSession = z.infer<typeof resetAgentSessionSchema>;
 
 export const testAdapterEnvironmentSchema = z.object({
+  runner: z.enum(["auto", "paperclip", "legacy"]).optional(),
   aiConnection: aiConnectionBindingSchema.optional(),
   /** Saved agent whose redacted environment entries are restored for this probe. */
   agentId: z.string().guid().optional(),