Merge remote-tracking branch 'origin/master' into worktree/semantic-session-checkpoints

# Conflicts:
#	docs/architecture.md
#	docs/event-producer-consumer.md
#	examples/acp-agent/tests/snapshots/cancel-tool-calls/session.jsonl
#	packages/core/agent-loop/README.md
#	packages/core/agent-loop/src/loop.ts
#	packages/core/agent-loop/tests/cancel.spec.ts

packages/session-persistence/session-checkpoint-policy/src/index.ts

@@ -7,7 +7,7 @@
 import type { Context } from 'cordis'
 import type { Session } from '@deepseek-ai/dsh-session'
 import type { StreamChunk } from '@deepseek-ai/dsh-llm'
-import type { ToolExecutionResult } from '@deepseek-ai/dsh-tools'
+import { TOOL_ABORTED_BEFORE_DISPATCH, type ToolExecutionResult } from '@deepseek-ai/dsh-tools'
 import type {} from '@deepseek-ai/dsh-agent'
 import type {} from '@deepseek-ai/dsh-session-persistence'
 
@@ -38,11 +38,11 @@ function afterCheckpoint(
 }
 
 /** Materialize the canonical result for a call cancelled before tool dispatch. */
-function abortedToolResult(): ToolExecutionResult {
+function abortedBeforeDispatchResult(): ToolExecutionResult {
   return {
-    content: [{ type: 'text', text: 'Error: tool call skipped because the step was aborted before execution' }],
+    content: [{ type: 'text', text: 'Error: tool call aborted before dispatch' }],
     isError: true,
-    error: { name: 'AbortError', code: 'ABORTED' },
+    error: { name: 'AbortError', code: TOOL_ABORTED_BEFORE_DISPATCH },
   }
 }
 
@@ -67,7 +67,7 @@ export function apply(ctx: Context): void {
   ctx.on('tools/execute', async (exec, next): Promise<ToolExecutionResult> => {
     if (exec.agent === undefined || exec.parent !== undefined) return next()
     await ctx.sessions.flush(exec.agent.session)
-    if (exec.signal?.aborted === true) return abortedToolResult()
+    if (exec.signal.aborted) return abortedBeforeDispatchResult()
     return next()
   })