PIR: Add vpn_connection_state to eligible pixels

[karlenDimla]

Task/Issue URL: https://app.asana.com/1/137249556945/task/1213085863198314

Description

See attached task description

Steps to test this PR

https://app.asana.com/1/137249556945/task/1213176315984932

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Note

Medium Risk
Touches analytics/pixel APIs and their call sites, requiring signature updates across production and tests; runtime risk is mitigated by wrapping VPN state lookup in runCatching and defaulting to false.

Overview
PIR now enriches eligible scan/opt-out result pixels with a new vpn_connection_state parameter (mapped to connected/disconnected) for PIR_SCAN_STAGE_RESULT_* and opt-out submit success/failure pixels.

RealPirRunStateHandler is updated to depend on NetworkProtectionState and safely query isRunning() (fail-closed) when emitting these pixels; tests and the end-to-end instrumentation setup add a FakeNetworkProtectionState, and pir-impl now depends on :network-protection-api.

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[karlenDimla]

• PIR: Add vpn_connection_state to eligible pixels #7704 👈 (View in Graphite)
• develop

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