Merge remote-tracking branch 'origin/master' into codex/rfc-subagent-background-tasks

# Conflicts:
#	docs/config-catalog.md
#	docs/module-graph.md
#	examples/coding-agent/README.md
#	examples/coding-agent/cordis.yml
#	packages/README.md
#	packages/examples/acp-demo/README.md
#	packages/examples/agent-spine-demo/README.md
#	packages/examples/agent-spine-demo/package.json
#	packages/examples/agent-spine-demo/src/index.ts
#	packages/examples/stdio-demo/README.md
#	pnpm-lock.yaml
#	scripts/doc-budgets.manifest.json
#	scripts/verify-package-readme-model-experience.ts

docs/rfc/INDEX.md

@@ -70,6 +70,7 @@ Generated by `pnpm run gen-rfc-index` from the RFC tree — never edit by hand;
 | [The approval seam — one-shot permission decisions over a waterfall of answerers](implemented/feature/2026-07-06-approval-seam.md) | 2026-07-06 |
 | [Explicit model-facing tool order](implemented/feature/2026-07-06-explicit-tool-order.md) | 2026-07-06 |
 | [The subprocess sandbox — confinement seam, native runners, escalation, and per-session modes](implemented/feature/2026-07-06-sandbox.md) | 2026-07-06 |
+| [MCP client plugin — connect to external MCP servers and bridge their tools](implemented/feature/2026-07-07-mcp-client-plugin.md) | 2026-07-07 |
 | [The session prefix — request-only messages in front of the derived history](implemented/feature/2026-07-07-session-prefix.md) | 2026-07-07 |
 | [Background subagent tasks](implemented/feature/2026-07-08-background-subagent-tasks.md) | 2026-07-08 |
 | [Repeat-tool-call guard plugin](implemented/feature/2026-07-08-repeat-tool-guard.md) | 2026-07-08 |