feat(routing): add tiers.yaml + rename spec/review-arch templates to airouter

W1 stage-routing work:
- model-registry/tiers.yaml: defines planning/spec-test/coding tier floors
  (complexity≥9/creativity≥9/context≥9 | spec_adherence≥9/test_pass_rate≥9 |
  spec_adherence≥7/test_pass_rate≥7) with qualifies_today lists
- spec-draft-airouter@2.yaml: honest name for what was spec-draft-opus@1
  (always ran Qwen3.6/airouter, not Opus)
- review-spec-arch-airouter@1.yaml: honest name for review-spec-arch-opus@1

Old @1 files kept for in-flight task backward-compatibility.

Claude-Session: https://claude.ai/code/session_01B35bPAKv5uyW1F9gzMcRN7

model-registry/tiers.yaml

@@ -0,0 +1,56 @@
+# Model capability tiers for typed-pipeline routing.
+#
+# Each tier defines score floors (against model-registry/*.yaml `scores` dimensions).
+# The CP picks the cheapest registry entry meeting ALL floors (MR-9/MR-11 — cheapest-wins).
+#
+# Stages that need a specific tier set `tier:` on their `kind: agent` node (W2).
+# Until W2 lands, templates hardcode `model:` directly and these floors serve as
+# documentation of the intended constraint.
+#
+# See claude/stage-routing.md for the authoritative pipeline stage map.
+
+tiers:
+
+  planning:
+    description: >
+      Judgment-heavy work: plan generation, spec re-draft (replan-spec-opus),
+      architecture review escalation (review-spec-opus). Requires sustained
+      reasoning over large context windows.
+    min_scores:
+      complexity: 9
+      creativity: 9
+      context_utilisation: 9
+    qualifies_today:
+      - deepseek-v4flash       # benchmark-inflated 9s; hold to allowed_models ceiling
+      - minimax
+      - claude-opus-4
+    note: >
+      WF-SCH-14 allowed_models ceiling remains authoritative until M7 observed-score
+      recalibration corrects benchmark-inflated registry entries.
+
+  spec-test:
+    description: >
+      Spec-adherent structured work: spec drafting, spec arch review, scope/decompose,
+      test writing, impl review, merge verdict. Needs reliable spec adherence and
+      test execution.
+    min_scores:
+      spec_adherence: 9
+      test_pass_rate: 9
+    qualifies_today:
+      - minimax
+      - claude-sonnet-4
+      - claude-opus-4
+
+  coding:
+    description: >
+      Narrow TDD implementation against pre-validated tests. Lower floors because
+      tests already constrain the solution space.
+    min_scores:
+      spec_adherence: 7
+      test_pass_rate: 7
+    qualifies_today:
+      - airouter-qwen3
+      - airouter-deepseekv4flash
+      - minimax
+      - claude-sonnet-4
+      - claude-opus-4

task-templates/workflow/review-spec-arch-airouter@1.yaml

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+name: review-spec-arch-airouter
+version: 1
+description: Architecture review of a spec draft
+runtime: best-practices-airouter-repo
+input:
+  state: spec-draft
+  tags_forbidden: [security-sensitive]
+  required_artifacts: [spec_file]
+output:
+  state: spec-reviewed-arch
+scope_budget:
+  files_modified_max: 2
+  lines_diff_max: 150
+  wall_clock_seconds_max: 1800
+nodes:
+  - id: agent
+    kind: agent
+    template: best-practices-airouter-repo
+    cli: agentic
+    model: Qwen3.6
+    labels: [airouter]
+    runtime_env:
+      AGENT_REPO_URL: "git@gitea.oreillyit.nz-ai-enablement:skynet/agent-runtimes-agents.git"
+      AGENT_BRANCH: "spec/auto-draft"
+    prompt: |
+      The agent-runtimes project repo is cloned at /workspace/project.
+      Change to that directory before doing any work.
+
+      Review the spec draft for the following concept.
+
+      **Title**: ${item.title}
+
+      **Original concept**:
+      ${item.body}
+
+      Steps:
+      1. cd /workspace/project
+      2. Find the spec file: ls spec/ and look for a file matching the concept title slug
+      3. Read the spec file completely
+      4. Review it against architectural best practices:
+         - Are requirements testable and unambiguous?
+         - Are there security implications not addressed?
+         - Are interfaces and data contracts clearly defined?
+         - Are edge cases and failure modes covered?
+      5. Write your review findings to /workspace/.agent-output/review.md with a PASS or
+         REWORK verdict and specific findings
+      6. Call task_complete with "PASS" or "REWORK: <one-line reason>"
+escalation:
+  contract_ambiguous: review-spec-opus

task-templates/workflow/spec-draft-airouter@2.yaml

@@ -0,0 +1,47 @@
+name: spec-draft-airouter
+version: 2
+description: Draft a spec from an idea using spec-writer agent
+runtime: spec-writing-airouter-repo
+input:
+  state: idea
+  tags_required: []
+  tags_forbidden: [security-sensitive]
+  required_artifacts: []
+output:
+  state: spec-draft
+scope_budget:
+  files_modified_max: 5
+  lines_diff_max: 300
+  wall_clock_seconds_max: 3600
+nodes:
+  - id: agent
+    kind: agent
+    template: spec-writing-airouter-repo
+    cli: agentic
+    model: Qwen3.6
+    labels: [airouter]
+    runtime_env:
+      AGENT_REPO_URL: "git@gitea.oreillyit.nz-ai-enablement:skynet/agent-runtimes-agents.git"
+      AGENT_BRANCH: "spec/auto-draft"
+    prompt: |
+      The agent-runtimes project repo is cloned at /workspace/project.
+      Change to that directory before doing any work.
+
+      Draft a spec for the following concept and commit it to the repo.
+
+      **Title**: ${item.title}
+
+      ${item.body}
+
+      Steps:
+      1. cd /workspace/project
+      2. Read existing specs in spec/ to understand the format
+      3. Create a slug from the title (lowercase, hyphens instead of spaces)
+      4. Write the spec to spec/<slug>.md following the project spec format
+      5. git add spec/<slug>.md && git commit -m "spec: auto-draft ${item.title}" && git push
+      6. Call task_complete with a one-sentence summary
+
+      The spec should have numbered requirement IDs, clear acceptance criteria,
+      and error handling. Follow the format of existing specs in spec/.
+escalation:
+  scope_exceeded: replan-spec-opus