feat: instance manifest, tool profiles, metrics, and budget enforcement

Land HARNESS-WP-0001 T01/T02/T04/T05: extend ADR-005 schedule.yml with
harness fields, named tool-profile registry, ADR-004 metrics writes, and
BudgetTracker wiring. CLI gains validate/profiles; task-file path kept.

examples/schedule.harness.yml

@@ -0,0 +1,30 @@
+# Example instance manifest (ADR-005 + agent-harness extensions).
+# Copy keys into a consuming repo's .kaizen/schedule.yml.
+# Validate with:
+#   agent-harness validate --target <repo> --strict
+version: "1"
+timezone: Europe/Berlin
+harness: 0
+agents:
+  coach:
+    cadence: daily
+    cron: "0 7 * * 1-5"
+    enabled: true
+    lane: green
+    tool_profile: green-commit-only
+    budget: 80000
+  mail-triage:
+    cadence: weekly
+    cron: "0 8 * * 1"
+    enabled: true
+    blueprint: coach
+    lane: blue
+    tool_profile: blue-mail-triage
+    budget: 40000
+  review-prep:
+    cadence: weekly
+    cron: "0 9 * * 5"
+    enabled: true
+    lane: green
+    tool_profile: green-commit-only
+    budget: 60000