Merge remote-tracking branch 'origin/master' into worktree/llm-reasoning-effort

# Conflicts:
#	.agents/notes/implemented/feature/2026-07-17-dedicated-full-screen-tui-front-door.i18n.yaml
#	docs/architecture.i18n.yaml
#	docs/core-data-structures/llm-streaming.i18n.yaml
#	docs/core-data-structures/session.i18n.yaml
#	docs/event-producer-consumer.md
#	examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/stdout.expected.jsonl

examples/headless-agent/tests/fixtures/semantic-checkpoint-agent.ts

@@ -0,0 +1,25 @@
+/**
+ * Loader fixture that publishes the semantic-checkpoint session before CLI dispatch.
+ * @module semantic-checkpoint-agent
+ */
+
+import type { Context } from 'cordis'
+import type { SessionId } from '@deepseek-ai/dsh-session'
+
+/** Fixture plugin name. */
+export const name = 'semantic-checkpoint-agent'
+/** Services that must exist before the fixture resumes its agent. */
+export const inject = ['agents', 'agentLoop', 'sessionPersistence']
+
+/**
+ * Resume the seeded session and bind its exact handle to this fixture's lifetime.
+ * @param ctx - settled agent and persistence services from the Loader tree.
+ * @returns after the resumed agent is published.
+ */
+export async function apply(ctx: Context): Promise<void> {
+  const handle = await ctx.agents.resume({
+    resumeSessionId: 'semantic-checkpoint-unknown-outcome' as SessionId,
+    agentOptions: { provider: 'deepseek', model: 'deepseek-v4-flash' },
+  })
+  ctx.effect(() => () => handle.dispose(), 'semantic-checkpoint-agent.handle')
+}