fix: T4 browser-check findings, interval on season state, T6 plan refresh

- Honey batch create omits an empty batch number (was 400); product form
  labels the legacy total weight, detail shows jar weight and shelf life;
  bottling hints next to their fields, values cleared on product change,
  post-save water-content wording; withdraw reason placeholder not
  selectable; honey batch actions offline-disabled with reason, 44 px.
- Offline signal: one slow request no longer flips the app offline; two
  consecutive timeouts do, any HTTP answer clears it, aborts never count.
- Phenology sheet as a side card on desktop with focus return; confirm
  dialogs as alertdialog; step-up texts in du-form ("Das Passwort stimmt
  nicht."); backup import gives its disabled reason; missing event labels
  plus a guard test; profile buttons 44 px.
- GET /phenology/state returns intervalDays via the shared
  inspectionIntervalOf (autopilot, digest, season state use one source).
- T6 plan aligned with the code after T4, plus owner decisions of
  2026-10-15 (Berlin day for restrictions, COMPLIANCE category, override
  without step-up).

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

ApiCore-Frontend/src/lib/auth/step-up-error.spec.ts

@@ -12,8 +12,8 @@ describe("stepUpErrorText", () => {
   });
 
   it("passes a German reauth message through unchanged", () => {
-    expect(stepUpErrorText(new ApiError(401, "Das Passwort ist falsch."), "x")).toBe(
-      "Das Passwort ist falsch.",
+    expect(stepUpErrorText(new ApiError(401, "Das Passwort stimmt nicht."), "x")).toBe(
+      "Das Passwort stimmt nicht.",
     );
   });