feat(templates): 6-tier escalation ladder — add MiniMax + Fable tiers

New tiers in the coding queue:
  airouter(0-2) → minimax(3-5) → sonnet(6-7) → opus(8-9) → fable(10) → blocked(11+)

- models/claude-fable-5.yaml: Fable 5 model definition (Anthropic cloud, claude runner)
- harnesses/composites/code-fable-tdd-repo/v1: Fable TDD composite (mirrors opus, anthropic-cloud-paul-oauth auth)
- model-registry/harness-roles.yaml: claude-fable-5 → code-fable-tdd-repo under code-tdd role
- model-registry/tiers.yaml: claude-fable-5 added to coding.qualifies_today
- task-templates/workflow/minimax-impl-ready@1.yaml: MiniMax TDD workflow (scope: 3 files / 200 lines / 30m)
- task-templates/workflow/fable-impl-ready@1.yaml: Fable TDD workflow (scope: 5 files / 400 lines / 60m)

Claude-Session: https://claude.ai/code/session_015sCpoFee3LsLKbHQ4FRRWY

harnesses/composites/code-fable-tdd-repo/v1/harness.yaml

@@ -0,0 +1,13 @@
+kind: composite
+name: code-fable-tdd-repo
+version: 1
+description: "Fable code agent with TDD enforcement — tests locked read-only, must pass before finish (last-resort tier)"
+layers:
+  - context: code-methodology/v1
+  - context: anthropic-cloud-paul-oauth/v1
+  - context: gitea-ssh/v1
+  - context: agent-repo/v1
+  - context: tdd-protect/v1
+  - context: tdd-gate/v1
+  - capability: python-dev/v1
+  - capability: tdd-file-lock/v1

model-registry/harness-roles.yaml

@@ -6,3 +6,4 @@ roles:
     claude-opus-4: code-opus-tdd-repo
     claude-haiku-4: code-haiku-tdd-repo
     minimax: code-minimax-tdd-repo
+    claude-fable-5: code-fable-tdd-repo

model-registry/tiers.yaml

@@ -54,3 +54,4 @@ tiers:
       - minimax
       - claude-sonnet-4
       - claude-opus-4
+      - claude-fable-5

models/claude-fable-5.yaml

@@ -0,0 +1,15 @@
+name: claude-fable-5
+provider: anthropic
+endpoint:
+  type: cloud_api
+  api_key_env: ANTHROPIC_API_KEY
+runner: claude
+default_flags:
+  model: "claude-fable-5"
+scores:
+  complexity: 10
+  creativity: 10
+  context_utilisation: 10
+  spec_adherence: 10
+  test_pass_rate: 10
+cost_per_1k_tokens: 0.05

task-templates/workflow/fable-impl-ready@1.yaml

@@ -0,0 +1,22 @@
+name: fable-impl-ready
+version: 1
+description: Impl of a spec requirement against pre-validated tests, Fable in worktree (final-tier escalation before blocked)
+runtime: code-fable-tdd-repo
+input:
+  state: scaffolded
+  tags_forbidden: [security-sensitive]
+  required_artifacts: []
+output:
+  state: impl-green
+scope_budget:
+  files_modified_max: 5
+  lines_diff_max: 400
+  wall_clock_seconds_max: 3600
+nodes:
+  - id: agent
+    kind: agent
+    template: code-fable-tdd-repo
+    runtime_env:
+      AGENT_REPO_URL: "git@gitea.oreillyit.nz-ai-enablement:skynet/agent-runtimes-agents.git"
+      AGENT_BRANCH: "task/${item.uuid}"
+    prompt: "Implement the task. ${metadata.automation.test_files}${metadata.automation.spec_ids}Task description: ${artifacts.item_title}. ${artifacts.item_body}"

task-templates/workflow/minimax-impl-ready@1.yaml

@@ -0,0 +1,22 @@
+name: minimax-impl-ready
+version: 1
+description: Impl of a spec requirement against pre-validated tests, MiniMax in worktree (second-tier escalation from airouter)
+runtime: code-minimax-tdd-repo
+input:
+  state: scaffolded
+  tags_forbidden: [security-sensitive]
+  required_artifacts: []
+output:
+  state: impl-green
+scope_budget:
+  files_modified_max: 3
+  lines_diff_max: 200
+  wall_clock_seconds_max: 1800
+nodes:
+  - id: agent
+    kind: agent
+    template: code-minimax-tdd-repo
+    runtime_env:
+      AGENT_REPO_URL: "git@gitea.oreillyit.nz-ai-enablement:skynet/agent-runtimes-agents.git"
+      AGENT_BRANCH: "task/${item.uuid}"
+    prompt: "Implement the task. ${metadata.automation.test_files}${metadata.automation.spec_ids}Task description: ${artifacts.item_title}. ${artifacts.item_body}"