after-pin: default skill_contracts on (#3939)

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

changelog.d/capy-gst-1088-flip-contracts.md

@@ -0,0 +1 @@
+The skill contract check is now on by default (GST-1088): when a skill with a contract block ends without its required outputs, the Stop hook blocks once and names what is missing. Turn it off with `gstack-config set skill_contracts off` or `./setup --no-skill-contracts`.

lib/skill-route.ts

@@ -37,7 +37,7 @@ export const SWITCH_ENV: Record<SwitchName, string> = {
 /** Each switch's one default. setup, gstack-config and gstack-skill-route read it through `gstack-skill-route --default <switch>`; the hooks read it here. */
 export const SWITCH_DEFAULT: Record<SwitchName, 'on' | 'off'> = {
   skill_routing: 'on',
-  skill_contracts: 'off',
+  skill_contracts: 'on',
 };
 
 export function normalizeSwitch(raw: string | null | undefined): 'on' | 'off' | null {

test/setup-skill-hooks-gate.test.ts

@@ -194,9 +194,9 @@ describe('SWITCH_DEFAULT is the one default (a flip PR changes one line)', () =>
     expect(SWITCH_DEFAULT.skill_routing).toBe('on');
   });
 
-  test('pin: skill_contracts defaults to off today (a flip PR changes lib/skill-route.ts line 40 and this pin)', () => {
-    expect(original.split('\n')[39]).toBe("  skill_contracts: 'off',");
-    expect(SWITCH_DEFAULT.skill_contracts).toBe('off');
+  test('pin: skill_contracts defaults to on today (a flip PR changes lib/skill-route.ts line 40 and this pin)', () => {
+    expect(original.split('\n')[39]).toBe("  skill_contracts: 'on',");
+    expect(SWITCH_DEFAULT.skill_contracts).toBe('on');
   });
 
   test('every reader agrees with SWITCH_DEFAULT: gstack-config, setup, the routing hook and the Stop hook', () => {