[instructions] Sync instruction files with release v0.86.2

[github-actions]

Summary

This PR synchronizes internal instruction files under .github/aw/ with new documentation introduced in gh-aw release v0.86.2. Changes cover Cloud Hypervisor/AWF guidance, cache-memory custom validation scripting, new agentic-workflow frontmatter fields (workload-identity, cooldown), and expanded engine harness/watchdog documentation. No source code or workflow behavior is altered — this is a documentation-only sync.

Change Classification

• Type: docs
• Scope: .github/aw (instruction files)
• Breaking: No

Key Changes

File	Change	Impact
.github/aw/agent-runtime-instructions.md	Expanded Cloud Hypervisor guidance: virtiofsd provisioning, scoped /dev/kvm access, default VM resources (2 vCPUs/4096 MiB), network isolation, and a list of unsupported configuration options under Cloud Hypervisor.	Low
.github/aw/memory.md	Added documentation for validation.script custom validation in cache-memory/repo-memory, including timeout settings and a JS example.	Low
.github/aw/syntax-agentic.md	Documented new workload-identity: OTLP export field (Google-only, OIDC-to-cloud-token exchange) and new cooldown: runtime field (default true, 3-day dependency cooldown).	Medium
.github/aw/syntax-engine.md	Expanded harness sub-field docs: retry policy fields (max-retries, initial-delay-ms, backoff-multiplier, max-delay-ms) and new watchdog-timeout field, with a link to environment-variable reference.	Low

Impact Assessment

• No downstream code, schema, or compiled workflow behavior changes — updates are limited to instruction/reference markdown consumed by agentic tooling and contributors.
• Documentation now reflects frontmatter fields (workload-identity, cooldown, harness.watchdog-timeout) and Cloud Hypervisor constraints that already exist in the schema/compiler as of v0.86.2; keeps instructions in sync with actual supported syntax.

Commits

d683e61f7 [instructions] Sync instruction files with release v0.86.2
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[github-actions]

Great work on keeping the instruction documentation in sync with v0.86.2! 🎯 This PR brings the .github/aw/ reference docs up to date with recent feature additions across the ecosystem:

• Cloud Hypervisor runtime details (VM sizing, isolation, incompatibilities)
• Custom validation hooks for cache and repo memory
• OTLP workload-identity support for cloud token exchange
• Runtime cooldown field documentation

The audit trail is thorough—cross-referenced against the schema, verified existing docs do not need updates, and confirmed all four edited files stay within line limits. The changes are focused, accurate, and well-scoped. This looks ready to merge! 🚀

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