Fix z.set() field values now properly displaying in subject table and export

[david-roper]

Show z.set() record fields correctly in the subject table and its exports

Problem

Instrument records with a z.set() field showed the value as [object Set] in the subject table
(Data Hub → subject → Table), and every download from that page wrote it as {}.

The stored data was fine. The API saves a Set in libjs's serialized form, and useInstrumentRecords
parses the response with libjs's reviver, so the web client gets a real Set back. The bug was in
how the page turned that value into text:

• Table cell: called String(value), which gives "[object Set]".
• Downloads: used JSON.stringify, which writes a Set as {}.

The reviver is deliberately unchanged. The API and react-core need it to rebuild a real Set,
because z.set() validation rejects anything else.

Changes

apps/web

File	Change
src/utils/record-value.ts (new)	formatRecordValue(value): a Set becomes its values joined with ", "; anything else still goes through String(value).
src/routes/_app/datahub/$subjectId/table/index.tsx	Table cells use formatRecordValue instead of String.
src/hooks/useInstrumentVisualization.ts	When dl builds the export rows, it converts Set values with formatRecordValue, so every download option writes them as the table shows them.

Example: a Set of MONEY and FRIENDS now shows as MONEY, FRIENDS in the table and in every
download option (CSV, TSV, Excel, their "Long" versions, and JSON). CSV and TSV quote it because it
contains a comma. In JSON it is a string, not an array.

Tests

Unit (apps/web)

• src/utils/__tests__/record-value.test.ts (new): covers a Set, a Set revived from the API's
  stored form, an empty Set, and other values.
• src/hooks/__tests__/useInstrumentVisualization.test.ts: new set fields tests for the wide,
  long and JSON exports. The mock records are now built by a small factory and reset in
  beforeEach.

End-to-end (testing)

• src/pages/_app/instruments/render/$id.page.ts:
  • New completeHappinessQuestionnaireDissatisfied(causes): answers "No", fills in the required
    reason, and ticks the given causes in causesOfDissatisfaction, the questionnaire's z.set()
    field.
  • The slider steps moved into a private setHappinessSliders shared with
    completeHappinessQuestionnaire, which behaves as before.
• src/specs/instrument-completion.spec.ts: new z.set() fields group whose setup completes the
  questionnaire through the UI. That takes the Set through the form, the API and the database, and
  back into the web client.
  • One test checks the table cell reads MONEY, FRIENDS.
  • One test downloads the CSV and checks it contains "MONEY, FRIENDS".

The new unit and end-to-end tests fail without the fix. The table e2e test received
[object Set], and the export tests received {}.

Verification

• pnpm lint: passes.
• pnpm test: 143 files, 1167 tests pass.
• pnpm test:e2e: 175 tests pass.

Known gaps (not in this branch)

• Record summary view: InstrumentSummaryGroup in packages/react-core still shows a Set as
  {}.
• Record updates: InstrumentRecordsService.updateById in apps/api saves the parsed data
  without the serializer, so editing a record that has a Set field probably stores it wrongly.
• Group-wide export: the API's export was not checked for Set fields.
• Flaky test: the graph-tab test in testing/src/specs/subject-detail.spec.ts timed out once
  under a full-suite run. It passed in Firefox and on 3 Chromium retries, and it is unrelated to
  this change.

Closes issue #1543