Updates for runZero 5.0

[hdm]

Summary

Refactors every integration script to use the new Starlark API surface from platform #25553. Result: ~1,800 lines added, ~2,000 lines removed across 60 files.

Changes

• Migrated 26 scripts from hand-rolled customAttribute flattening to to_custom_attributes(...).
• Renamed every script to drop the custom-integration- / custom_integration_ / custom-integrations- filename prefix. Each directory now contains a <name>.star (e.g. tailscale.star, cisco-ise.star, boilerplate.star).
• Removed stale duplicate snipe-it/snipeit.star (pre-refactor copy).
• New integration: kubernetes — pulls Nodes (and optional LoadBalancer/NodePort Services) from the Kubernetes API using a ServiceAccount bearer token. Documented setup with kubectl create serviceaccount + view ClusterRole + kubectl create token.
• Restored TLS-skip path in tailscale.star (regression where INSECURE_SKIP_VERIFY wasn't being threaded through to oauth2_token / get_json).
• README updates:
  • New "Asset IDs and match behavior" section documenting no-{id,mac,ip,name}-{match,break} tokens with three recommended match_behavior presets (default, "stable identifiers but unstable name/mac/ip", "always create new").
  • Added Kubernetes link to the integration index.
• Convention docs (AGENTS.md, pull_request_template.md) updated to describe the new <integration-name>.star naming convention.
• Cross-references in integrations.json, starlark-helpers.md, and individual integration READMEs updated to point at the new filenames.

Validation

Pre-merge validator (go run /tmp/parse_integrations/main.go against the platform's ValidateStarlarkProgram): 39 files checked, 0 failures.