feat: add orch-* orchestrator skill family (#2153)

* feat: add orch-* orchestrator skill family

Lightweight wrappers that orchestrate existing ECC agents through a gated Research -> Plan -> TDD -> Review -> Commit pipeline, right-sized per task.

- orch-pipeline: shared engine (phases, size classifier, two gates, agent map)
- orch-add-feature/change-feature/fix-defect/refine-code/build-mvp: thin wrappers delegating to the engine

* chore: register orch-* family in catalog, command registry, and agent.yaml (post-rebase onto green main)

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Co-authored-by: ECC Test <ecc@example.test>

skills/orch-refine-code/SKILL.md

@@ -0,0 +1,43 @@
+---
+name: orch-refine-code
+description: Orchestrate a behavior-preserving refactor — confirm tests are green, restructure without changing behavior, keep tests green, review, and gated commit. Use when the structure should improve but behavior must not change.
+origin: ECC
+---
+
+# orch-refine-code
+
+Actor · action · target: **orch · refine · code**. Thin wrapper over the shared
+engine in [`orch-pipeline`](../orch-pipeline/SKILL.md).
+
+## When to Use
+
+- Same behavior, **better structure**: extract modules, remove duplication, kill
+  dead code, reduce nesting, rename for clarity.
+- Distinguish from siblings: if behavior is meant to change at all, this is the
+  wrong skill (`orch-change-feature` / `orch-fix-defect`).
+
+## Operation settings
+
+- **Default size floor:** standard — restructures touch multiple files.
+- **Phase mask:** 0 → 2 (plan the restructure) → 4 (keep green) → 5 → 6. No new
+  behavior tests are written — the existing suite is the safety net.
+- **First move (phase 4):** confirm the relevant tests exist and are **green
+  before** touching code; if coverage is thin, add characterization tests first.
+  Then restructure in small steps, re-running tests after each.
+
+## How It Works
+
+1. Run the `orch-pipeline` engine with the settings above.
+2. For dead-code / duplication sweeps, delegate to the `refactor-cleaner` agent
+   (it runs knip / depcheck / ts-prune and removes safely).
+3. Stop at **Gate 1** (restructure plan) and **Gate 2** (pre-commit).
+4. Commit as `refactor:` — the diff must be behavior-neutral.
+
+## Example
+
+```
+orch-refine-code: extract the NWS HTTP client out of poller.py
+→ confirm tests green → plan extraction  [GATE 1: approve]
+→ move in small steps, tests green throughout → code-review
+→ commit refactor:  [GATE 2: confirm]
+```