feat(skill-routing): default the routing hook on (GST-1088)

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

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

@@ -0,0 +1 @@
+The skill routing hook is now on by default (GST-1088): a prompt that fits an installed gstack skill gets a one-line hint naming it. Turn it off with `gstack-config set skill_routing off` or `./setup --no-skill-routing`.

lib/skill-route.ts

@@ -36,7 +36,7 @@ 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: 'off',
+  skill_routing: 'on',
   skill_contracts: 'off',
 };
 

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

@@ -189,9 +189,9 @@ describe('SWITCH_DEFAULT is the one default (a flip PR changes one line)', () =>
     expect(config()).toBe('');
   }
 
-  test('pin: skill_routing defaults to off today (a flip PR changes lib/skill-route.ts line 39 and this pin)', () => {
-    expect(original.split('\n')[38]).toBe("  skill_routing: 'off',");
-    expect(SWITCH_DEFAULT.skill_routing).toBe('off');
+  test('pin: skill_routing defaults to on today (a flip PR changes lib/skill-route.ts line 39 and this pin)', () => {
+    expect(original.split('\n')[38]).toBe("  skill_routing: 'on',");
+    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)', () => {