[AZ-455] Decompose Step 3 — test task specs (AZ-457..AZ-482)

Adds 26 blackbox-test task specs under epic AZ-455 plus the matching
rows in _dependencies_table.md. Each task depends on AZ-456 (test
infrastructure). Advances autodev existing-code flow Step 5 → Step 6
(Implement Tests, cycle 1) ready for batch implementation.

Co-authored-by: Cursor <cursoragent@cursor.com>

_docs/02_tasks/todo/AZ-473_test_photo_mode.md

@@ -0,0 +1,54 @@
+# Test — PhotoMode Switch & yoloId Wire
+
+**Task**: AZ-473_test_photo_mode
+**Name**: PhotoMode switch + auto-select + yoloId offsetting on the wire
+**Description**: Implement the 3 blackbox tests pinning PhotoMode behavior: switching modes sets the offset filter, auto-selecting when the prior class is no longer valid, and the on-wire `classNum == classId + photoModeOffset` assertion.
+**Complexity**: 2 points
+**Dependencies**: AZ-456_test_infrastructure
+**Component**: 06_annotations (PhotoModeContext + AnnotationsPage) (Blackbox Tests)
+**Tracker**: AZ-473
+**Epic**: AZ-455
+
+## Problem
+
+PhotoMode offsets `classId` to `classNum` on the wire (`classNum == classId + photoModeOffset`). Getting this wrong leaks a different class on every save without any user-visible symptom — until a downstream consumer mis-buckets the data.
+
+## Outcome
+
+- 3 scenarios pass — mode switch, auto-select on invalid, wire offset arithmetic.
+
+## Scope
+
+### Included
+
+| Scenario | Profile | Source file |
+|----------|---------|-------------|
+| FT-P-48 — PhotoMode switch — mode set + filter | fast | blackbox-tests.md |
+| FT-P-49 — PhotoMode auto-select when prior class no longer valid | fast | blackbox-tests.md |
+| FT-P-50 — yoloId on the wire — `classNum == classId + photoModeOffset` | fast + e2e | blackbox-tests.md |
+
+### Excluded
+
+- DetectionClasses load + hotkeys (covered in 17_test_detection_classes).
+
+## Acceptance Criteria
+
+**AC-1: Switch sets filter**
+FT-P-48 — toggling PhotoMode updates the rendered class list (filter applied); the selected mode is persisted in `<PhotoModeContext>` (asserted via the rendered filter, not via context read).
+
+**AC-2: Auto-select**
+FT-P-49 — switching to a mode where the currently-selected class is out-of-range auto-selects the first valid class in the new window.
+
+**AC-3: Wire offset**
+FT-P-50 — issue an annotation save in mode P; outbound body carries `classNum == classId + P` for every detection.
+
+## System Under Test Boundary
+
+- System under test: `<PhotoModeContext>` + `<AnnotationsPage>` save call.
+- Allowed stubs: MSW for `/api/annotations/classes` + annotation save.
+- Disallowed: reading `<PhotoModeContext>` state directly.
+- Expected observables per `results_report.md` rows 77-80 region.
+
+## Constraints
+
+- Tests exercise all three modes (P ∈ {0, 20, 40}); each saves a probe annotation and asserts the wire offset.