feat(cli): add --workspace filter to 'dispatch list'

The backend already supported GET /conversations?workspaceId= but the CLI
never sent it. Wire the list command to that filter:

- args.ts: parse --workspace / -w on 'list' (placed before the --catch-all
  so the single-dash -w shorthand isn't taken for a positional prefix);
  add workspaceId? to the list ParsedCommand.
- http.ts: add workspaceId? to FetchConversationsOpts; send ?workspaceId=
  (after q/status, preserving URLSearchParams order).
- main.ts: forward parsed.workspaceId into fetchConversations; update USAGE.

Composable with --status and the <prefix> short-id arg. 'Open conversations
in workspace X' is now: dispatch list --workspace X  (status defaults to
active,idle). No contract changes — purely additive CLI wiring.

Tests: +4 args (incl. composability + missing-value error), +2 http
(exact ?workspaceId= URL + combined status/workspaceId with %2C encoding).
typecheck EXIT 0, biome clean (364 files), full suite 1558 passed.
Live-verified against an isolated server.

5 files changed, 75 insertions, 1 deletions

diff --git a/packages/cli/src/args.test.ts b/packages/cli/src/args.test.ts
index 7a45c02..e613f31 100644
--- a/packages/cli/src/args.test.ts
+++ b/packages/cli/src/args.test.ts
@@ -254,6 +254,41 @@ describe("parseArgs", () => {
 			});
 		});
 
+		it("parses 'list' with --workspace", () => {
+			expect(parseArgs(["list", "--workspace", "proj"], { defaultServer })).toEqual({
+				kind: "list",
+				server: "http://localhost:24203",
+				workspaceId: "proj",
+				all: false,
+			});
+		});
+
+		it("parses 'list' with -w shorthand", () => {
+			const result = parseArgs(["list", "-w", "ws"], { defaultServer });
+			expect(result.kind).toBe("list");
+			if (result.kind === "list") expect(result.workspaceId).toBe("ws");
+		});
+
+		it("parses 'list' with --workspace, --status, and a prefix together", () => {
+			const result = parseArgs(["list", "abc", "--status", "active", "--workspace", "proj"], {
+				defaultServer,
+			});
+			expect(result).toEqual({
+				kind: "list",
+				server: "http://localhost:24203",
+				query: "abc",
+				status: "active",
+				workspaceId: "proj",
+				all: false,
+			});
+		});
+
+		it("errors when --workspace has no value (list)", () => {
+			const result = parseArgs(["list", "--workspace"], { defaultServer });
+			expect(result.kind).toBe("error");
+			if (result.kind === "error") expect(result.message).toContain("--workspace requires a value");
+		});
+
 		it("parses 'list' with --all", () => {
 			expect(parseArgs(["list", "--all"], { defaultServer })).toEqual({
 				kind: "list",
diff --git a/packages/cli/src/args.ts b/packages/cli/src/args.ts
index aaad2de..74cc56a 100644
--- a/packages/cli/src/args.ts
+++ b/packages/cli/src/args.ts
@@ -33,6 +33,7 @@ export type ParsedCommand =
 			readonly server: string;
 			readonly query?: string;
 			readonly status?: string;
+			readonly workspaceId?: string;
 			readonly all: boolean;
 	  }
 	| { readonly kind: "compact"; readonly server: string; readonly conversationId: string }
@@ -85,6 +86,7 @@ export function parseArgs(argv: readonly string[], opts: ParseOpts): ParsedComma
 		let server = opts.defaultServer;
 		let query: string | undefined;
 		let status: string | undefined;
+		let workspaceId: string | undefined;
 		let all = false;
 		for (let i = 1; i < argv.length; i++) {
 			const arg = argv[i] as string;
@@ -94,6 +96,9 @@ export function parseArgs(argv: readonly string[], opts: ParseOpts): ParsedComma
 			} else if (arg === "--status") {
 				if (i + 1 >= argv.length) return { kind: "error", message: "--status requires a value" };
 				status = argv[++i];
+			} else if (arg === "--workspace" || arg === "-w") {
+				if (i + 1 >= argv.length) return { kind: "error", message: "--workspace requires a value" };
+				workspaceId = argv[++i];
 			} else if (arg === "--all") {
 				all = true;
 			} else if (arg.startsWith("--")) {
@@ -109,6 +114,7 @@ export function parseArgs(argv: readonly string[], opts: ParseOpts): ParsedComma
 			server,
 			...(query !== undefined && { query }),
 			...(status !== undefined && { status }),
+			...(workspaceId !== undefined && { workspaceId }),
 			all,
 		};
 	}
diff --git a/packages/cli/src/http.test.ts b/packages/cli/src/http.test.ts
index 2aa61e9..ab39813 100644
--- a/packages/cli/src/http.test.ts
+++ b/packages/cli/src/http.test.ts
@@ -289,6 +289,36 @@ describe("fetchConversations", () => {
 		expect(calledUrl).toBe("http://localhost:24203/conversations?q=abc+def");
 	});
 
+	it("appends ?workspaceId=<value> when a workspaceId is given", async () => {
+		let calledUrl: string | undefined;
+		const fakeFetch = (async (url: string | URL | Request): Promise<Response> => {
+			calledUrl = String(url);
+			return new Response(JSON.stringify({ conversations: [] }), { status: 200 });
+		}) as unknown as typeof fetch;
+
+		await fetchConversations(
+			{ fetchImpl: fakeFetch },
+			{ server: "http://localhost:24203", workspaceId: "proj" },
+		);
+		expect(calledUrl).toBe("http://localhost:24203/conversations?workspaceId=proj");
+	});
+
+	it("combines ?status= and ?workspaceId= when both are given", async () => {
+		let calledUrl: string | undefined;
+		const fakeFetch = (async (url: string | URL | Request): Promise<Response> => {
+			calledUrl = String(url);
+			return new Response(JSON.stringify({ conversations: [] }), { status: 200 });
+		}) as unknown as typeof fetch;
+
+		await fetchConversations(
+			{ fetchImpl: fakeFetch },
+			{ server: "http://localhost:24203", status: "active,idle", workspaceId: "proj" },
+		);
+		expect(calledUrl).toBe(
+			"http://localhost:24203/conversations?status=active%2Cidle&workspaceId=proj",
+		);
+	});
+
 	it("throws on non-OK status", async () => {
 		const fakeFetch = (async (): Promise<Response> =>
 			new Response("boom", { status: 500 })) as unknown as typeof fetch;
diff --git a/packages/cli/src/http.ts b/packages/cli/src/http.ts
index 42fcfec..e13842a 100644
--- a/packages/cli/src/http.ts
+++ b/packages/cli/src/http.ts
@@ -98,6 +98,7 @@ interface FetchConversationsOpts {
 	readonly server: string;
 	readonly query?: string;
 	readonly status?: string;
+	readonly workspaceId?: string;
 }
 
 export async function fetchConversations(
@@ -107,6 +108,7 @@ export async function fetchConversations(
 	const params = new URLSearchParams();
 	if (opts.query !== undefined) params.set("q", opts.query);
 	if (opts.status !== undefined) params.set("status", opts.status);
+	if (opts.workspaceId !== undefined) params.set("workspaceId", opts.workspaceId);
 	const qs = params.toString();
 	const url = qs.length > 0 ? `${opts.server}/conversations?${qs}` : `${opts.server}/conversations`;
 	const res = await deps.fetchImpl(url);
diff --git a/packages/cli/src/main.ts b/packages/cli/src/main.ts
index b61be07..cba0de7 100644
--- a/packages/cli/src/main.ts
+++ b/packages/cli/src/main.ts
@@ -24,7 +24,7 @@ import { extractLastText, formatConversationList, renderEvent } from "./render.j
 
 const USAGE = `Usage:
   dispatch models [--server <url>]
-  dispatch list [<prefix>] [--status <active|idle|closed>] [--all] [--server <url>]
+  dispatch list [<prefix>] [--status <active|idle|closed>] [--workspace <id>] [--all] [--server <url>]
   dispatch stop <conversationId> [--server <url>]
   dispatch compact <conversationId> [--server <url>]
   dispatch read <conversationId> [--server <url>]
@@ -61,6 +61,7 @@ async function main(): Promise<void> {
 					server: parsed.server,
 					...(parsed.query !== undefined && { query: parsed.query }),
 					...(status !== undefined && { status }),
+					...(parsed.workspaceId !== undefined && { workspaceId: parsed.workspaceId }),
 				},
 			);
 			const table = formatConversationList(result.conversations, Date.now());