chore: release 9.7.1

[alpertarhan]

Release 9.7.1 with the issue #72 verification/extraction fix.

• Bump package and extension version to 9.7.1.
• Move issue Verification gate permanently fails-closed on re-compacted sessions: prior-summary text (completed items, superseded rules, own error messages) re-extracted as live constraints #72 fix notes into dated changelog.
• Explicitly record user-approved stable release exception: required 20 applied canary runs have not been collected.
• Fix a Pi 0.87 widened test type in window-boundary coverage.

Validation: bun run release:check passed. Additional compatibility, audit, provider-eval, telemetry, and pack checks running.