fix(approvals): usertest-panel hardening (0.81.0)

Panel findings against the reworked approvals page, fixed in place:

- Never fabricate the request time: ApprovalRecord.createdAt is
  nullable now; a missing created_at omits the line instead of
  rendering DateTime.now() (which drifted on refresh). Guard:
  approvals_origin_test pins the omit-on-null invariant.
- Copyable errors on approve/reject/batch via showChainErrorSnack
  (the hard project rule) — batch surfaces the first real cause.
- Reject requires a reason: ChainInlineHelp strip + confirm disabled
  while empty, no more silent close-and-nothing-happens.
- Batch approve applies the same no-data confirmation as the single
  path, naming how many selected requests carry no show: data.
- Plainer language: glossary "Vorgang (Flow)", history label FRAGE
  (was PROMPT), no-data hint drops developer jargon.
- One-click copy of the run id; history payload pretty-prints like
  the card.

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

CHANGELOG.md

@@ -28,6 +28,31 @@ lockstep.
   local CLI falls back to it. Guard: two new `RunsLoadErrorView`
   widget tests.
 
+### Fixed (0.81.0)
+
+Approvals usertest-panel hardening:
+
+- **Never fake the request time.** A missing/unparseable `created_at`
+  now leaves the "Angefordert" line off the card instead of showing
+  `now` (which even drifted on every refresh). `ApprovalRecord.createdAt`
+  is nullable; guard in `approvals_origin_test`.
+- **Copyable errors on every path.** Approve/Reject and both batch
+  actions now route failures through `showChainErrorSnack` instead of
+  a bare `SnackBar(Text(e))` — the batch path surfaces the first real
+  cause, not just a count.
+- **Reject needs a reason.** The reject dialog leads with a
+  `ChainInlineHelp` strip and disables the confirm button while the
+  reason is empty, instead of closing silently with nothing happening.
+- **Batch approve respects the no-data guard.** A bulk approve that
+  includes requests without `show:` data now asks for the same
+  conscious confirmation the single approve already required, naming
+  how many are data-less.
+- **Plainer language.** The intro and origin glossary "Flow" as
+  "Vorgang (Flow)", the history detail labels the question "FRAGE"
+  (not "PROMPT"), and the no-data hint drops developer jargon.
+- **Copy the run id in one click**, and the history payload renders
+  with the same JSON pretty-printing as the card.
+
 ### Added (0.80.0)
 
 - **Ollama joins the host services.** Ollama-backed store entries