fix: plan mode exception for review log + telemetry writes

Add explicit plan-mode exception notes to review log sections in all
3 plan review skill templates and the telemetry section in gen-skill-docs.ts.
When Claude runs in plan mode, it self-censors bash writes — but review
logging and telemetry write to ~/.gstack/ (user metadata, not project
files). The preamble already writes to the same directory successfully.
The exception note gives Claude a reasoning chain: safety argument,
precedent, and consequence of skipping.

test/gen-skill-docs.test.ts

@@ -449,6 +449,7 @@ describe('telemetry', () => {
     expect(content).toContain('_TEL_DUR');
     expect(content).toContain('SKILL_NAME');
     expect(content).toContain('OUTCOME');
+    expect(content).toContain('PLAN MODE EXCEPTION');
   });
 
   test('generated SKILL.md contains pending marker handling', () => {