docs: record bounded activity authorization evidence

Co-Authored-By: Paperclip <noreply@paperclip.ing>

doc/plans/2026-10-13-connection-api-parity.md

@@ -167,3 +167,5 @@ The implementation was rebased onto `a1f77821b9cd5c9c846fdf7a0fa5cc620ad2b6bb`.
 - Failed GitHub secret replacements retain the prior copy only after its committed generation is confirmed unchanged. A changed or unreadable generation blocks copying and reconnecting; an explicit status check can restore the earlier copy when the server confirms it. All three new replacement cases were red before the fix; all **82 GitHub UI tests passed** afterward. Cloud enrollment map entries now name instance-admin creation/callback checks and distinguish the HTML/303 browser return. Maps and UI token gates passed. Fresh successor CI and reviews remain required before merging.
 
 - Master advanced to `c7c12dbc79` while the review fixes were being qualified. Its published Copilot v62 identity is preserved byte-for-byte. The combined delegated connection guidance uses v63 with digest `sha256:f29dc04c3217ad74aeaf96b2c466d5a1dc6c55942f5bd4db9c1cf52f2985d19e`; the shared identity generator and **60 Copilot installation tests passed**. The first root-level invocation selected no Runner tests; the package configuration ran the intended suite. Migration 0379 is unchanged by this merge.
+
+- A later security review found that activity reads authorized the entire endpoint conversation history before applying the activity limit. The real run-JWT regression measured **200 checks before the fix and one afterward** for the same one-item page. The query now selects only conversations referenced by the bounded activity candidates, deduplicates issue decisions, and reuses the request's run read context. The focused regression is green; a fresh complete suite and current-head CI remain required.