Stop repo lanes from executing the wrong task payload

The next repo-local sweep target was ROADMAP #71: a claw-code lane
accepted an unrelated KakaoTalk/image-analysis prompt even though the
lane itself was supposed to be repo-scoped work. This extends the
existing prompt-misdelivery guardrail with an optional structured task
receipt so worker boot can reject visible wrong-task context before the
lane continues executing.

Constraint: Keep the fix inside the existing worker_boot / WorkerSendPrompt control surface instead of inventing a new external OMX-only protocol
Rejected: Treat wrong-task receipts as generic shell misdelivery | loses the expected-vs-observed task context needed to debug contaminated lanes
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: If task-receipt fields change later, update the WorkerSendPrompt schema, worker payload serialization, and wrong-task regression together
Tested: cargo fmt --all --check; cargo clippy --workspace --all-targets -- -D warnings; cargo test --workspace; architect review APPROVE
Not-tested: External orchestrators that have not yet started populating the optional task_receipt field

rust/crates/tools/src/lib.rs

@@ -20,7 +20,7 @@ use runtime::{
     summary_compression::compress_summary_text,
     task_registry::TaskRegistry,
     team_cron_registry::{CronRegistry, TeamRegistry},
-    worker_boot::{WorkerReadySnapshot, WorkerRegistry},
+    worker_boot::{WorkerReadySnapshot, WorkerRegistry, WorkerTaskReceipt},
     write_file, ApiClient, ApiRequest, AssistantEvent, BashCommandInput, BashCommandOutput,
     BranchFreshness, ConfigLoader, ContentBlock, ConversationMessage, ConversationRuntime,
     GrepSearchInput, LaneCommitProvenance, LaneEvent, LaneEventBlocker, LaneEventName,
@@ -930,7 +930,22 @@ pub fn mvp_tool_specs() -> Vec<ToolSpec> {
                 "type": "object",
                 "properties": {
                     "worker_id": { "type": "string" },
-                    "prompt": { "type": "string" }
+                    "prompt": { "type": "string" },
+                    "task_receipt": {
+                        "type": "object",
+                        "properties": {
+                            "repo": { "type": "string" },
+                            "task_kind": { "type": "string" },
+                            "source_surface": { "type": "string" },
+                            "expected_artifacts": {
+                                "type": "array",
+                                "items": { "type": "string" }
+                            },
+                            "objective_preview": { "type": "string" }
+                        },
+                        "required": ["repo", "task_kind", "source_surface", "objective_preview"],
+                        "additionalProperties": false
+                    }
                 },
                 "required": ["worker_id"],
                 "additionalProperties": false
@@ -1522,7 +1537,11 @@ fn run_worker_await_ready(input: WorkerIdInput) -> Result<String, String> {
 
 #[allow(clippy::needless_pass_by_value)]
 fn run_worker_send_prompt(input: WorkerSendPromptInput) -> Result<String, String> {
-    let worker = global_worker_registry().send_prompt(&input.worker_id, input.prompt.as_deref())?;
+    let worker = global_worker_registry().send_prompt(
+        &input.worker_id,
+        input.prompt.as_deref(),
+        input.task_receipt,
+    )?;
     to_pretty_json(worker)
 }
 
@@ -2439,6 +2458,8 @@ struct WorkerSendPromptInput {
     worker_id: String,
     #[serde(default)]
     prompt: Option<String>,
+    #[serde(default)]
+    task_receipt: Option<WorkerTaskReceipt>,
 }
 
 const fn default_auto_recover_prompt_misdelivery() -> bool {