fix(gen): resolver registry describes the template language again

Seven registered {{PLACEHOLDER}}s had zero uses in any .tmpl (checked in both
bare and :arg forms): REDACT_TAXONOMY_TABLE, TEST_COVERAGE_AUDIT_REVIEW,
MODEL_OVERLAY, QUESTION_PREFERENCE_CHECK, QUESTION_LOG, INLINE_TUNE_FEEDBACK,
MAKE_PDF_SETUP. The last two of those families are invoked programmatically by
preamble.ts (functions kept, registry entries dropped); the question-tuning
trio and the review coverage-audit wrapper were documented by their own module
as existing 'for unit testing' that no test performed — deleted, along with
generateRedactTaxonomyTable + its EXAMPLE/TIER_BLURB constants (its '/cso
renders the full table' comment was itself stale) and its test describe.

Also deletes the gated-resolver mechanism (ResolverEntry/appliesTo/
unwrapResolver + test/resolver-entry.test.ts): fully built, fully tested,
used by zero of the 65 registry entries — the generator loop simplifies to a
direct function call. CLAUDE.md's redact-doc line stops advertising the dead
token.

Proof: zero-diff regen (0 SKILL.md changed); gen-skill-docs + skill-validation
737 tests green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

scripts/gen-skill-docs.ts

@@ -14,7 +14,7 @@ import { writeLlmsTxt } from './gen-llms-txt';
 import * as fs from 'fs';
 import * as path from 'path';
 import type { Host, TemplateContext } from './resolvers/types';
-import { HOST_PATHS, unwrapResolver } from './resolvers/types';
+import { HOST_PATHS } from './resolvers/types';
 import { RESOLVERS } from './resolvers/index';
 import { ALL_HOST_CONFIGS, ALL_HOST_NAMES, resolveHostArg, getHostConfig } from '../hosts/index';
 import type { HostConfig } from './host-config';
@@ -683,10 +683,8 @@ function resolvePlaceholders(
       const resolverName = parts[0];
       const args = parts.slice(1);
       if (suppressed.has(resolverName)) return '';
-      const entry = RESOLVERS[resolverName];
-      if (!entry) throw new Error(`Unknown placeholder {{${resolverName}}} in ${relTmplPath}`);
-      const { resolve, appliesTo } = unwrapResolver(entry);
-      if (appliesTo && !appliesTo(ctx)) return '';
+      const resolve = RESOLVERS[resolverName];
+      if (!resolve) throw new Error(`Unknown placeholder {{${resolverName}}} in ${relTmplPath}`);
       return args.length > 0 ? resolve(ctx, args) : resolve(ctx);
     });