test: derive paid touchfiles from each eval's static closure (E)

touchfiles.test.ts now checks, per key, that the paid file's static
test/helpers and test/fixtures closure (plus fixture paths it names in string
literals) is covered, and names the file, path, chain and key to fix when it is
not. Free *.test.ts files are no longer touchfiles, so editing a free replay
test stops selecting paid evals: 950 entries removed, 653 real closure paths
added. The hand-copied inventories go: periodic-fixture-selection,
fake-impeccable-touchfiles and 45 per-file selection examples. Selection for
the sample edits (plan-eng-review template, claude-pty-runner,
plan-count-fixture, gstack-config) loses no case under either profile.
CONTRIBUTING documents the rule and its lower bound.

test/design-research-fixture.test.ts

@@ -1,8 +1,6 @@
 import { expect, test } from 'bun:test';
 import { readFileSync } from 'node:fs';
 import { extractDesignResearchContract } from './helpers/skill-fixture';
-import { E2E_TOUCHFILES, selectTests } from './helpers/touchfiles';
-
 const source = readFileSync(new URL('../design-consultation/SKILL.md', import.meta.url), 'utf8');
 
 test('research-only fixture supplies actual readiness and egress dependencies without expanding scope', () => {
@@ -23,9 +21,3 @@ test.each(['## BROWSER SETUP', '### Rules for driving a real browser', '## Web r
   '## Phase 2: Research', '**Step 1: Identify', '**Step 2: Visual research', '_aside_exec()'])('missing %s fails closed before a paid run', marker => {
   expect(() => extractDesignResearchContract(source.replace(marker, 'REMOVED'))).toThrow();
 });
-
-test('research fixture changes select their actual live consumer', () => {
-  for (const file of ['test/helpers/skill-fixture.ts', 'test/design-research-fixture.test.ts']) {
-    expect(selectTests([file], E2E_TOUCHFILES, []).selected).toContain('design-consultation-research');
-  }
-});