docs(plan): multiple simultaneous approval requests in one turn

Plan-only workspace for removing the one-approval-per-turn latch so each gated
tool call in a turn emits its own approval card, pluralizing the parked-approval
record and the warm/keep-alive resume path, and verifying the already-plural
frontend and SDK behavior with tests.

Plans #5373, assesses #5078 and #5097.

Claude-Session: https://claude.ai/code/session_01DnWRxU3dCJ11hgDidm26vW

Author: mmabrouk