Update demo replay validation and testing documentation

- Modified the autodev state to reflect the current testing phase and details of the new `jetson-e2e` tests.
- Enhanced the "How to Test" documentation to provide clearer instructions on the demo replay validation process, including video and tlog alignment steps.
- Updated architectural documentation to include the new demo replay operator flow and its dependencies.
- Documented the removal of deprecated auto-sync features and clarified the operator-facing UI for replay validation.
- Added new entries in the dependencies table for upcoming tasks related to the demo replay flow.

These changes improve clarity and usability for operators and developers working with the demo replay system.

.cursor/skills/decompose/steps/04_cross-verification.md

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+# Step 4: Cross-Task Verification (implementation and tests-only modes)
+
+**Role**: Professional software architect and analyst
+**Goal**: Verify task consistency and produce `_dependencies_table.md`.
+**Constraints**: Review step — fix gaps found, do not add new tasks.
+
+## Steps
+
+1. Verify task dependencies across all tasks are consistent
+2. Check no gaps:
+   - In implementation mode: every product interface in `architecture.md` has implementation task coverage
+   - In tests-only mode: every test scenario in `traceability-matrix.md` is covered by a task
+   - In implementation mode: every named internal runtime capability/dependency from architecture, solution, system flows, and component descriptions has a production implementation task, not only an interface/scaffold/fallback task
+   - In tests-only mode: every e2e/blackbox task has a System Under Test Boundary section that forbids stubbing internal product modules and requires comparison to expected-results artifacts
+3. Check no overlaps: tasks don't duplicate work
+4. Check no circular dependencies in the task graph
+5. Produce `_dependencies_table.md` using `templates/dependencies-table.md`
+
+## Self-verification
+
+### Implementation mode
+
+- [ ] Every product interface in `architecture.md` is covered by at least one implementation task
+- [ ] Every named internal runtime capability has a production implementation task
+- [ ] No circular dependencies in the task graph
+- [ ] Cross-component dependencies are explicitly noted in affected task specs
+- [ ] `_dependencies_table.md` contains every task with correct dependencies
+
+### Tests-only mode
+
+- [ ] Every test scenario from `traceability-matrix.md` "Covered" entries has a corresponding task
+- [ ] Every e2e/blackbox task validates actual product behavior and allows stubs only for external systems
+- [ ] No circular dependencies in the task graph
+- [ ] Test task dependencies reference the test infrastructure bootstrap
+- [ ] `_dependencies_table.md` contains every task with correct dependencies
+
+## Save action
+
+Write `_dependencies_table.md`.
+
+## Blocking
+
+**BLOCKING**: Present dependency summary to user. Do NOT proceed until user confirms.