feat: add runtime network llm governance finding

[CoderDeltaLAN]

Adds AIRK-GOV005 for supported instruction files that encourage runtime network, LLM, or external API use in conflict with the local-first boundary.

Summary:

• adds conservative runtime network / LLM / external API guidance detection
• reports path and line for risky guidance
• ignores explicit no-network/no-LLM/no-external-API boundaries
• ignores supported instruction filename mentions such as CLAUDE.md and GEMINI.md
• keeps human planning/review usage outside runtime unflagged
• updates stable governance rule order

Boundary:

• does not add network behavior
• does not add LLM behavior
• does not execute repository commands
• does not touch README, release, tag, CI, dependencies, workflows, docs, or branch protection

Verification:

• ./scripts/check.sh
• targeted AIRK-GOV005 unit tests
• isolated build and wheel install smoke