feat: add ci test runner, session routing, bash parser, and test fixtures

- script/run-ci-tests.ts: CI test sharding and isolation logic
- script/run-ci-tests.test.ts: tests for CI test target selection
- src/features/background-agent/session-route.ts: session prompt routing for background agents
- src/hooks/interactive-bash-session/parser.ts: interactive bash output parser
- src/hooks/ralph-loop/completion-promise-detector-test-input.ts: test fixture for completion promise detection

src/features/background-agent/session-route.ts

@@ -0,0 +1,72 @@
+import type { PluginInput } from "@opencode-ai/plugin"
+
+import { promptWithModelSuggestionRetry } from "../../shared"
+import { promptAsyncAfterSessionIdle } from "../../shared/prompt-async-gate"
+
+type OpencodeClient = PluginInput["client"]
+
+type PromptAsyncArgs = Parameters<OpencodeClient["session"]["promptAsync"]>[0]
+type PromptRetryClient = Parameters<typeof promptWithModelSuggestionRetry>[0]
+type PromptRetryArgs = Parameters<typeof promptWithModelSuggestionRetry>[1]
+type SessionMessagesArgs = Parameters<OpencodeClient["session"]["messages"]>[0]
+
+export function routeSessionPrompt(args: PromptAsyncArgs, directory: string): PromptAsyncArgs {
+  return {
+    ...args,
+    query: { directory },
+  }
+}
+
+function routePromptRetry(args: PromptRetryArgs, directory: string): PromptRetryArgs {
+  return {
+    ...args,
+    query: { directory },
+  }
+}
+
+export function promptAsyncInDirectory(
+  client: OpencodeClient,
+  args: PromptAsyncArgs,
+  directory: string,
+): Promise<unknown> {
+  const routedArgs = routeSessionPrompt(args, directory)
+  const sessionID = routedArgs.path?.id
+  if (!sessionID) {
+    return Promise.reject(new Error("session id is required for routed promptAsync"))
+  }
+
+  return promptAsyncAfterSessionIdle({
+    client,
+    sessionID,
+    input: routedArgs,
+    source: "background-agent-session-route",
+    settleMs: 0,
+  }).then((result) => {
+    if (result.status === "failed") {
+      throw result.error
+    }
+    if (result.status !== "dispatched") {
+      throw new Error(`promptAsync skipped by gate: ${result.status}`)
+    }
+    return result.response
+  })
+}
+
+export function promptWithRetryInDirectory(
+  client: PromptRetryClient,
+  args: PromptRetryArgs,
+  directory: string,
+): Promise<void> {
+  return promptWithModelSuggestionRetry(client, routePromptRetry(args, directory))
+}
+
+export function messagesInDirectory(
+  client: OpencodeClient,
+  args: SessionMessagesArgs,
+  directory: string,
+): Promise<unknown> {
+  return client.session.messages({
+    ...args,
+    query: { directory },
+  })
+}