chore: WIP pre-implement

Bundled hygiene commit before cycle-3 /implement (AZ-776, AZ-777). Mixes
two concerns by user choice (autodev option B):

- Cycle-3 autodev artifacts not yet committed by Step 9 (new-task):
  task specs for AZ-776 / AZ-777 under _docs/02_tasks/todo/ and the
  updated _docs/02_tasks/_dependencies_table.md.
- Accumulated skill / rule tooling maintenance under .cursor/ (skills:
  autodev, code-review, decompose, deploy, implement, new-task, plan,
  refactor, retrospective, test-spec; rules: coderule, cursor-meta,
  meta-rule, testing; new release skill scaffolding).
- Autodev bootstrap state: _docs/_autodev_state.md (step 10 in_progress)
  and _docs/_process_leftovers/2026-05-11_d_cross_cve_1_opencv_pin_deferred.md
  (replay timestamp refreshed; gtsam 4.2 still numpy<2-only).

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

.cursor/skills/plan/SKILL.md

@@ -15,7 +15,7 @@ disable-model-invocation: true
 
 # Solution Planning
 
-Decompose a problem and solution into architecture, data model, deployment plan, system flows, components, tests, and work item epics through a systematic 6-step workflow.
+Decompose a problem and solution into architecture, data model, deployment plan, system flows, components, ADRs, tests, and work item epics through a systematic workflow with seven step files (1, 2, 3, 4, 4.5, 5, 6) plus a Final quality checklist.
 
 ## Core Principles
 
@@ -55,7 +55,7 @@ Read `steps/01_artifact-management.md` for directory structure, save timing, sav
 
 ## Progress Tracking
 
-At the start of execution, create a TodoWrite with all steps (1 through 6 plus Final). Update status as each step completes.
+At the start of execution, create a TodoWrite with all steps (1, 2, 3, 4, 4.5, 5, 6 plus Final). Update status as each step completes. The fractional Step 4.5 (ADR Capture) sits between Architecture Review (Step 4) and Test Specifications (Step 5).
 
 ## Workflow
 
@@ -85,6 +85,16 @@ Read and follow `steps/04_review-risk.md`.
 
 ---
 
+### Step 4.5: Architecture Decision Records (ADRs)
+
+Read and follow `steps/04-5_adr-capture.md`.
+
+This step captures the architecture and tech-stack decisions that were made (or revised) in Steps 2–4 as durable, dated, immutable records under `_docs/02_document/adr/`. ADRs are the single thing in `_docs/` that explain the **why** of each major decision after the conversation history is gone. They are consumed by `decompose` (when bootstrapping module layout), `new-task` (when assessing a new feature against existing decisions), `refactor` (when proposing replacements), and any future code-review cycle that needs to confirm a structural choice was deliberate.
+
+This step is **BLOCKING**: the ADR set must be reviewed and confirmed by the user before Step 5 begins.
+
+---
+
 ### Step 5: Test Specifications
 
 Read and follow `steps/05_test-specifications.md`.
@@ -120,7 +130,7 @@ Read and follow `steps/07_quality-checklist.md`.
 |-----------|--------|
 | Missing acceptance_criteria.md, restrictions.md, or input_data/ | **STOP** — planning cannot proceed |
 | Ambiguous requirements | ASK user |
-| Input data coverage below 75% | Search internet for supplementary data, ASK user to validate |
+| Input data coverage below the canonical threshold (`cursor-meta.mdc` Quality Thresholds) | Search internet for supplementary data, ASK user to validate |
 | Technology choice with multiple valid options | ASK user |
 | Component naming | PROCEED, confirm at next BLOCKING gate |
 | File structure within templates | PROCEED |
@@ -146,6 +156,8 @@ Read and follow `steps/07_quality-checklist.md`.
 │    [BLOCKING: user confirms components]                        │
 │ 4. Review & Risk       → risk register, iterations              │
 │    [BLOCKING: user confirms mitigations]                       │
+│ 4.5 ADR Capture        → _docs/02_document/adr/NNN_*.md         │
+│    [BLOCKING: user confirms ADR set]                           │
 │ 5. Test Specifications → per-component test specs               │
 │ 6. Work Item Epics     → epic per component + bootstrap         │
 │    ─────────────────────────────────────────────────           │