feat(coding-agent): enabled importing foreign sessions from claude and codex

- Implemented session stores and metadata converters to import Claude and Codex sessions into OMP.
- Added `--from-claude` and `--from-codex` CLI flags and `/resume` command arguments for foreign session resolution.
- Updated session selector components and controllers to support listing and picking external agent sessions.
- Added comprehensive unit tests and documentation covering foreign session import functionality.

packages/coding-agent/src/cli/args.ts

@@ -44,6 +44,8 @@ export interface Args {
 	advisor?: boolean;
 	continue?: boolean;
 	resume?: string | true;
+	fromClaude?: boolean;
+	fromCodex?: boolean;
 	help?: boolean;
 	version?: boolean;
 	mode?: Mode;
@@ -227,6 +229,10 @@ export function parseArgs(inputArgs: string[], extensionFlags?: Map<string, { ty
 			result.alias = arg.slice("--alias=".length);
 		} else if (arg === "--continue" || arg === "-c") {
 			result.continue = true;
+		} else if (arg === "--from-claude") {
+			result.fromClaude = true;
+		} else if (arg === "--from-codex") {
+			result.fromCodex = true;
 		} else if (arg === "--no-session") {
 			result.noSession = true;
 		} else if (arg === "--no-tools") {

packages/coding-agent/src/cli/flag-tables.ts

@@ -290,6 +290,8 @@ export const VALUELESS_FLAGS: ReadonlySet<string> = new Set([
 	"--version",
 	"--allow-home",
 	"--continue",
+	"--from-claude",
+	"--from-codex",
 	"--no-session",
 	"--no-tools",
 	"--no-lsp",

packages/coding-agent/src/cli/session-picker.ts

@@ -6,16 +6,26 @@ import type { SessionInfo } from "../session/session-listing";
 import { SessionManager } from "../session/session-manager";
 import { FileSessionStorage } from "../session/session-storage";
 
+/** Presentation and capability controls for the standalone session picker. */
+export interface SessionPickerOptions {
+	allSessions?: SessionInfo[];
+	title?: string;
+	scopeLabel?: string | false;
+	showCwd?: boolean;
+	allowDelete?: boolean;
+	allowGlobalScope?: boolean;
+	historySearch?: boolean;
+}
+
 /**
  * Show the TUI session selector and return the selected session, or null if
- * cancelled. Rendered as a fullscreen overlay on the terminal's alternate
- * screen, so the list scrolls and rows are clickable with the mouse. Tab
- * toggles between current-folder and all-projects scope; the all-projects list
- * is loaded lazily via `SessionManager.listAll`.
+ * cancelled. The default OMP picker supports deletion, transcript-history
+ * search, and an all-projects scope; foreign import pickers disable those
+ * source-owned capabilities.
  */
 export async function selectSession(
 	sessions: SessionInfo[],
-	options?: { allSessions?: SessionInfo[] },
+	options: SessionPickerOptions = {},
 ): Promise<SessionInfo | null> {
 	const { promise, resolve } = Promise.withResolvers<SessionInfo | null>();
 	const ui = new TUI(new ProcessTerminal());
@@ -26,11 +36,13 @@ export async function selectSession(
 	// session-list prefix never sees. Best-effort: a missing/locked history.db
 	// must not break the picker.
 	let historyMatcher: ((query: string) => string[]) | undefined;
-	try {
-		const history = HistoryStorage.open();
-		historyMatcher = (query: string) => history.matchingSessionIds(query);
-	} catch (error) {
-		logger.warn("History storage unavailable for session ranking", { error: String(error) });
+	if (options.historySearch !== false) {
+		try {
+			const history = HistoryStorage.open();
+			historyMatcher = (query: string) => history.matchingSessionIds(query);
+		} catch (error) {
+			logger.warn("History storage unavailable for session ranking", { error: String(error) });
+		}
 	}
 
 	const showSelector = () => {
@@ -58,16 +70,21 @@ export async function selectSession(
 				}
 			},
 			{
-				onDelete: async (session: SessionInfo) => {
-					// Delete handler - SessionList will show confirmation internally
-					await storage.deleteSessionWithArtifacts(session.path);
-					return true;
-				},
+				onDelete:
+					options.allowDelete === false
+						? undefined
+						: async (session: SessionInfo) => {
+								await storage.deleteSessionWithArtifacts(session.path);
+								return true;
+							},
 				historyMatcher,
-				loadAllSessions: () => SessionManager.listAll(storage),
-				allSessions: options?.allSessions,
+				loadAllSessions: options.allowGlobalScope === false ? undefined : () => SessionManager.listAll(storage),
+				allSessions: options.allSessions,
 				getTerminalRows: () => ui.terminal.rows,
 				fillHeight: true,
+				title: options.title,
+				scopeLabel: options.scopeLabel,
+				showCwd: options.showCwd,
 			},
 		);
 		return selector;