docs: purge chain-of-thought leakage from prose

Delete design-session citations (decision/audit/plan ordinals, stack
positions), change narration, review choreography, and reviewer-addressed
justification from comments, JSDoc, docs, READMEs, Agent Notes, tests, and
generator templates; restate every affected fact as current-state contract
prose. Fix generated docs at their sources and regenerate the catalogs and
cordis-surface regions; re-paste type-equiv blocks; update every bilingual
counterpart and re-record the pairs. Record the citation rule in the
committed-artifact-citations Agent Note.

packages/credentials/credentials-local/tests/local.spec.ts

@@ -130,8 +130,8 @@ describe('layer ladder', () => {
       { source: 'user-env', path: '/home/.dsh/.env', values: { DSH_CRED_TEST: 'older-user-env' } },
     ])
     expect(await ctx.credentials.resolve(KEY)).toEqual({ value: 'stored', source: 'file' })
-    // The old dead end is gone: a key sitting in the user's .env no longer
-    // makes the stored one unwritable.
+    // A key sitting in the user's .env does not make the stored one
+    // unwritable.
     expect(await ctx.credentials.describe(KEY)).toEqual({ configured: true, source: 'file', writable: true })
     await expect(ctx.credentials.set(KEY, 'rotated')).resolves.toBeUndefined()
     expect(await ctx.credentials.resolve(KEY)).toEqual({ value: 'rotated', source: 'file' })