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

# Conflicts:
#	docs/architecture.md
#	docs/config-catalog.md
#	docs/cordis-catalog/services.md
#	docs/core-data-structures/bash.md
#	docs/event-producer-consumer.md
#	docs/rfc/implemented/feature/2026-07-06-sandbox.md
#	docs/rfc/proposed/architecture/2026-06-20-generic-long-running-tool-runtime.md
#	examples/AGENTS.md
#	examples/acp-agent/tests/snapshots/advanced-toolchain/session.1.jsonl
#	examples/acp-agent/tests/snapshots/advanced-toolchain/session.2.jsonl
#	examples/acp-agent/tests/snapshots/advanced-toolchain/session.jsonl
#	examples/acp-agent/tests/snapshots/advanced-toolchain/system-prompt.golden.md
#	examples/acp-agent/tests/snapshots/both-mode-turn/session.jsonl
#	examples/acp-agent/tests/snapshots/both-mode-turn/system-prompt.golden.md
#	examples/acp-agent/tests/snapshots/code-mode-turn/system-prompt.golden.md
#	examples/acp-agent/tests/snapshots/permission-switching/system-prompt.golden.md
#	examples/acp-agent/tests/snapshots/skill-load/session.jsonl
#	examples/acp-agent/tests/snapshots/skill-load/system-prompt.golden.md
#	examples/acp-agent/tests/snapshots/text-turn/session.jsonl
#	examples/acp-agent/tests/snapshots/text-turn/system-prompt.golden.md
#	examples/coding-agent/cordis.yml
#	examples/sandbox-acp-agent/tests/snapshots/escalation-approved/session.jsonl
#	examples/sandbox-acp-agent/tests/snapshots/escalation-rejected/session.jsonl
#	examples/sandbox-acp-agent/tests/snapshots/mode-switching/session.jsonl
#	packages/bash/bash-local/README.md
#	packages/bash/bash-local/src/index.ts
#	packages/bash/bash-local/tests/executor.spec.ts
#	packages/bash/bash-sandbox/README.md
#	packages/bash/bash-sandbox/src/index.ts
#	packages/bash/bash/README.md
#	packages/bash/bash/src/index.ts
#	packages/bash/bash/src/types.ts
#	packages/bash/tool-bash/README.md
#	packages/bash/tool-bash/src/index.ts
#	packages/bash/tool-bash/tests/tools.spec.ts
#	packages/cordis/tool-cordis/src/api-catalog.ts
#	packages/core/agent-core/README.md
#	packages/core/agent-core/src/index.ts
#	packages/subagent/subagent/README.md
#	packages/subagent/tool-subagent/README.md
#	packages/subagent/tool-subagent/src/index.ts
#	packages/ui/acp-agent/README.md
#	packages/ui/acp/README.md
#	packages/ui/stdio-agent/README.md
#	packages/util/brand/src/index.ts
#	scripts/doc-budgets.manifest.json

packages/core/agent-core/README.md

@@ -2,7 +2,7 @@
 
 The **default executor-less, UI-less agent spine** as ONE Cordis bundle plugin. It loads the fixed set of services every harness agent needs, including the local skill provider, and forwards the loop's `agents` list as its own config — so an app package composes a working agent by adding only a front door and the swappable backends.
 
-This is the package to read to see **the whole plugin tree at once** — the teaching role the inlined `echo-agent` `cordis.yml` used to play before the spine moved behind this bundle.
+Read this package for the whole plugin tree and its composition order.
 
 ## The tree it loads
 
@@ -50,4 +50,13 @@ The bundle FORWARDS each field to the child that owns it: `agents` to `agent-loo
 
 ## Why a code bundle, not a shared YAML include
 
-A YAML include can dedupe the config, but it cannot OWN a `bin`, and it can only *describe* the front-door coupling in a comment and trust each leaf to obey. Moving the spine into a package, and the front-door cluster into the app packages, means the default leaf for an ACP server has no logger entry to copy wrong — "the ACP app never logs to stdout" stops being a prose warning a leaf must remember and becomes the app package's default shape (a leaf can still add a sibling logger, so the rule stays documented — but it has nothing to get wrong by default). Services register in the root store keyed by their isolate symbol, so a child loaded here is visible to the bundle's siblings (the leaf's adapter and executor) exactly as a nested `plugin-include` subtree's services were — cordis gates every read on `inject`, never on load order.
+A YAML include can deduplicate config but cannot own a bin or provide front-door defaults. App packages make stdout-safe ACP wiring the default, though a leaf can still add an unsafe logger. Bundle children register services in the root isolate-keyed store, so injected leaf siblings see them without load-order coupling.
+
+## Model Experience
+
+Indirectly, through `dsh-system-prompt`, `dsh-tool-skill`, `dsh-tool-bash`, and `dsh-tools`, which this bundle mounts without adding model-bound wrapper content.
+
+## Known Limitations and Deferred Work
+
+- **The spine set is fixed in code** — `apply()` mounts every child unconditionally (including `tool-bash`); no config excludes or replaces one, so swapping the loop or dropping a spine member means composing a different bundle.
+- **`dsh-invariants` mounts unconditionally** — this bundle has no toggle, so every composition using it pays the dev-mode relational assertions; Session's always-on validation and freezing are separate.