feat(store): advisory-version badge for federated entries

Store cards + detail-sheet now prefix the version pill with
`~` and attach a tooltip for federated entries (MCP / n8n /
Temporal). Upstream services don't honour semver, so the
version pill is a label, not a contract — the tilde says
"this number may change without a version bump."

Three render sites updated to stay visually consistent:
- compact card pill in grid view
- expanded card pill row
- detail-sheet header pill cluster

EN + DE l10n entries added (`storeAdvisoryVersionTooltip`)
and `app_localizations.dart` regenerated.

dart analyze clean; flutter test green (11 tests).

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

lib/l10n/app_en.arb

@@ -779,6 +779,7 @@
       }
     }
   },
+  "storeAdvisoryVersionTooltip": "Federated upstream service — version is advisory; the upstream may break compatibility without bumping it.",
   "maintenanceHeader": "HUB MAINTENANCE",
   "maintenanceResetBlurb": "Wipe operator state and start over with a clean hub. Stops every running daemon, atomically backs ~/.fai/ up, then recreates it with the binary, channel state, MCP / n8n / system-AI config, and registry token preserved. Restore by moving the backup directory back.",
   "maintenanceKeepModulesTitle": "Keep installed modules",