test(bal): Group E - mock tests with fake wallet giovanna7

Add tests/test_group_e_mock_giovanna7.py (22 GUI-free tests) driven by a
self-contained fake wallet named giovanna7, covering four areas:

- E1 calendar/.ics: reminder-offset distribution (compute_reminder_offsets),
  VALARM/TRIGGER shape (TRIGGER;RELATED=END:-P{n}D), iCalendar escaping, and
  temporary .ics file creation.
- E2 inheritance/states: loading/adding/removing heirs (Heirs), WillItem
  status transitions (VALID->COMPLETE, INVALIDATED clears VALID, PUSHED clears
  PUSH_FAIL), Will.only_valid, and heir-change detection.
- E3 connectivity: stubbed get_info_task proving ping_servers_parallel runs
  concurrently, fires on_each once per server with the right ok flag, and
  writes results back; plus empty-mapping no-op.
- E4 will-executor: is_selected default/set, get_willexecutor_transactions
  filtering (only VALID+COMPLETE+not-PUSHED+selected; force re-includes PUSHED),
  and compute_id.

CHANGELOG: add entry #9. ruff clean; full suite 239 passed.

CHANGELOG.md

@@ -582,3 +582,38 @@ starting on the Desktop) instead of opening it. (D2 was intentionally skipped.)
   branching.
 
 **Verification (follow-up):** full suite `217 passed`.
+
+## 9. Group E - Mock tests with fake wallet "giovanna7"
+
+**Goal:** add automated, GUI-free mock tests covering four behaviour areas of
+the plugin, all driven by a single self-contained fake wallet named
+"giovanna7" (no real Electrum wallet file is needed).
+
+**What was added:**
+
+- `tests/test_group_e_mock_giovanna7.py` (new) - 22 tests in four sections:
+  - A fake wallet model (`GiovannaWallet`, `FakeDB`) whose `str(wallet)` is
+    `"giovanna7"`, pre-loaded with two heirs (alice, bob).
+  - **E1 - calendar / .ics:** reminder-offset distribution rules
+    (`compute_reminder_offsets`), VALARM/TRIGGER shape
+    (`TRIGGER;RELATED=END:-P{n}D`), iCalendar escaping of the event text, and
+    writing a temporary `.ics` file (`BalCalendar.write_temp_ics`).
+  - **E2 - inheritance / states:** loading/adding/removing giovanna7's heirs
+    (`Heirs`), and `WillItem` status transitions (VALID -> COMPLETE,
+    INVALIDATED clears VALID, PUSHED clears PUSH_FAIL), `Will.only_valid`, and
+    heir-change detection (`HeirNotFoundException`).
+  - **E3 - connectivity:** stubbing `Willexecutors.get_info_task` to prove that
+    `ping_servers_parallel` contacts giovanna7's servers concurrently (total
+    time far below the sequential sum), fires the per-server `on_each` callback
+    once with the correct ok flag, and writes results back into the mapping;
+    plus the empty-mapping no-op.
+  - **E4 - will-executor:** `is_selected` default/set behaviour, the
+    `get_willexecutor_transactions` filtering rule (only VALID + COMPLETE +
+    not-PUSHED + selected wills are pushed; `force=True` re-includes PUSHED
+    ones), and `compute_id`.
+
+**Verification:**
+- `ruff check` on the new test file: clean (all checks passed).
+- Full test suite: `239 passed` (217 previous + 22 new Group E tests).
+
+**Outcome:** DONE (delivered as a ZIP for user testing before commit).