refactor(reviewer): slim reviewer.md and verify skill to reduce token load

- reviewer.md: remove default hypothesis, After APPROVED block, and
  Available Skills list — all duplicated from verify/SKILL.md which is
  always loaded in the same session (ai-agents.md #24, #26)
- verify/SKILL.md v4.0:
  - drop Standards Summary table (pure restatement of inline content)
  - drop 'When to Use' section (no information beyond skill name)
  - OC size/nesting rules (5d rules 1 and 7) cross-reference 6b thresholds
    instead of repeating values
  - replace 5d OC table with design-patterns skill reference (on-demand
    loading per ai-agents.md #23); commitment-device structure preserved
    inside that skill
  - move Self-Declaration Audit to Step 5 (before code review) — if SE
    flagged a DISAGREE, reviewer saves all of code review before rejecting
  - DISAGREE handling: triage gate instead of hard reject — accepts
    genuine out-of-SE-control constraints with a note and suggested
    alternative; rejects weak/unjustified deviations with specific fix
  - renumber code review sub-sections 5a-5g → 6a-6g

Author: nullhack

.opencode/skills/verify/SKILL.md

@@ -17,11 +17,7 @@ This skill guides the reviewer through Step 4: independent verification that the
 
 **You never move `.feature` files.** After producing an APPROVED report: update TODO.md `Next:` to `Run @product-owner — accept feature <name> at Step 5.` then stop. The PO accepts the feature and moves the file.
 
-## When to Use (Step 4)
-
-After the software-engineer signals Step 3 is complete and all self-verification checks pass. Do not start verification until the software-engineer has committed all work and communicated the Self-Declaration verbally in the handoff message.
-
-The reviewer produces one written report (see template below) that includes: all gate results, the SE Self-Declaration Audit, the **Reviewer Stance Declaration**, and the final APPROVED/REJECTED verdict.
+The reviewer produces one written report (see template below) that includes: all gate results, the SE Self-Declaration Audit, the **Reviewer Stance Declaration**, and the final APPROVED/REJECTED verdict. Do not start until the software-engineer has committed all work and communicated the Self-Declaration verbally in the handoff message.
 
 ## Step-by-Step
 
@@ -163,18 +159,6 @@ If the feature involves user interaction: run the app, provide real input, verif
 
 Record what input was given and what output was observed.
 
-### 8. Self-Declaration Audit
-
-Read the software-engineer's Self-Declaration from the handoff message.
-
-For every **AGREE** claim:
-- Find the `file:line` — does it hold?
-
-For every **DISAGREE** claim:
-- REJECT — the software-engineer must fix before requesting review again.
-
-Undeclared violations → REJECT.
-
 ### 9. Write the Report
 
 ```markdown