refactor(voice): extract reusable Pocket primitives + Pocket voice settings (relands #2467 + #3208) (#3910)

Relands **#2467** (extract `buzz-voice` crate) and **#3208** (Pocket
voice settings) onto main, after #3266 and #3180 merged.

## Why a fresh PR
The repo is squash-only with delete-branch-on-merge. Squashing #3266
deleted `jtennant/pocket-tts-2026-04`, which was #2467's base — GitHub
auto-closed #2467 and it cannot be reopened. Squash merges also sever
ancestry, so GitHub's natural merge-base reports phantom conflicts for
the whole remaining stack.

## Content provenance
- Byte-identical to the blessed `jt/buzz-voice-refactor` branch
(`93029c577`, tree `6729e0eff` — reviewed by Dawn (#2467) and Max
(#3208) at exact heads) **except** the three files where #3180 and #3208
genuinely interact.
- Three-file resolution (union of both sides):
- `huddle/mod.rs` — #3180's pipeline re-exports + #3208's
`agent_tts_routing` imports.
- `huddle/state.rs` — `reset_preserving_generation` preserves both
`huddle_generation` (#3180) and `tts_enabled` (#3208); test sets merged
into one `tests` module.
- `desktop/src/testing/e2eBridge.ts` — both switch arms kept; no
duplicate case labels.

## Verification at cf32dacd7
- `cargo test` (desktop/src-tauri, pinned 1.95.0): **2047 + 3 pass / 0
fail** (14 ignored: 8 keychain, 4 real_relay, 2 flag-gated)
- `cargo clippy --all-targets -- -D warnings`: clean; `cargo fmt
--check`: clean
- `cargo check --workspace` (root, includes new `buzz-voice` member):
clean; `cargo test -p buzz-voice`: 5/0
- `pnpm test`: **3885 / 0**; `tsc --noEmit`: clean; lint: clean

The 3180×3208 interaction resolution is getting an independent team
re-review before merge.

Buzz channel: buzz-desktop-voice `fd5fb402-b651-4238-89b1-bb3e2fa4dc96`,
thread `b4798ecc`.

Signed-off-by: npub1qyvc0c5kl4gqv2fd97fsk46tu378sqgy35vc83rvgfwne90sel7s0ed67d <011987e296fd5006292d2f930b574be47c7801048d1983c46c425d3c95f0cffd@buzz.block.builderlab.xyz>
Co-authored-by: npub1qyvc0c5kl4gqv2fd97fsk46tu378sqgy35vc83rvgfwne90sel7s0ed67d <011987e296fd5006292d2f930b574be47c7801048d1983c46c425d3c95f0cffd@buzz.block.builderlab.xyz>

desktop/tests/e2e/voice-settings.spec.ts

@@ -0,0 +1,119 @@
+import { expect, test } from "@playwright/test";
+
+import { waitForAnimations } from "../helpers/animations";
+import { installMockBridge } from "../helpers/bridge";
+import { openSettings } from "../helpers/settings";
+
+const SCREENSHOT_PATH = "test-results/voice-settings/pocket-voices.png";
+
+test.describe("Pocket voice settings", () => {
+  test.use({ viewport: { width: 1100, height: 760 } });
+
+  test("selects and retains a bundled voice while text to speech is off", async ({
+    page,
+  }) => {
+    await installMockBridge(page);
+    await page.goto("/", { waitUntil: "domcontentloaded" });
+    await openSettings(page, "voice");
+
+    const card = page.getByTestId("settings-voice");
+    await expect(card).toBeVisible();
+    await expect(
+      page.getByText("Agent text to speech", { exact: true }),
+    ).toBeVisible();
+    await expect(
+      page.getByText("Pocket TTS voice", { exact: true }),
+    ).toBeVisible();
+    await expect(card).not.toContainText("April INT8");
+
+    await page.getByTestId("pocket-voice-selector").click();
+    await expect(page.getByRole("menuitemradio")).toHaveCount(12);
+    await page.getByRole("menuitemradio", { name: "Eve" }).click();
+    await expect(page.getByTestId("pocket-voice-selector")).toContainText(
+      "Eve",
+    );
+    await expect(
+      page.getByRole("button", { name: "Pocket TTS voice: Eve" }),
+    ).toBeVisible();
+
+    await page.getByTestId("agent-text-to-speech-toggle").click();
+    await expect(
+      page.getByTestId("agent-text-to-speech-toggle"),
+    ).toHaveAttribute("aria-checked", "false");
+    await expect(page.getByTestId("pocket-voice-controls")).toHaveAttribute(
+      "aria-disabled",
+      "true",
+    );
+    await expect(page.getByTestId("pocket-voice-selector")).toContainText(
+      "Eve",
+    );
+
+    const savedCommands = await page.evaluate(() =>
+      (window.__BUZZ_E2E_COMMAND_LOG__ ?? [])
+        .filter((entry) =>
+          ["set_pocket_voice", "set_tts_enabled"].includes(entry.command),
+        )
+        .map((entry) => ({ command: entry.command, payload: entry.payload })),
+    );
+    expect(savedCommands).toEqual([
+      {
+        command: "set_pocket_voice",
+        payload: { voiceKey: "pocket:eve" },
+      },
+      {
+        command: "set_tts_enabled",
+        payload: { enabled: false },
+      },
+    ]);
+  });
+
+  test("captures the complete VCTK preset settings surface", async ({
+    page,
+  }) => {
+    await installMockBridge(page, {
+      ttsSettings: {
+        version: 1,
+        agentTextToSpeech: true,
+        voicePreferences: ["pocket:eve"],
+      },
+    });
+    await page.goto("/", { waitUntil: "domcontentloaded" });
+    await openSettings(page, "voice");
+
+    const card = page.getByTestId("settings-voice");
+    await expect(card).toBeVisible();
+    await expect(page.getByTestId("pocket-voice-selector")).toContainText(
+      "Eve",
+    );
+    await page.getByTestId("pocket-voice-selector").click();
+    await expect(page.getByRole("menuitemradio")).toHaveCount(12);
+    const menu = page.getByRole("menu");
+    await expect(menu).toBeVisible();
+    await waitForAnimations(page);
+    const cardBox = await card.boundingBox();
+    const menuBox = await menu.boundingBox();
+    const viewport = page.viewportSize();
+    if (!cardBox || !menuBox || !viewport) {
+      throw new Error("Voice settings screenshot bounds are unavailable");
+    }
+    const x = Math.max(0, Math.min(cardBox.x, menuBox.x) - 16);
+    const y = Math.max(0, Math.min(cardBox.y, menuBox.y) - 16);
+    const right = Math.min(
+      viewport.width,
+      Math.max(cardBox.x + cardBox.width, menuBox.x + menuBox.width) + 16,
+    );
+    const bottom = Math.min(
+      viewport.height,
+      Math.max(cardBox.y + cardBox.height, menuBox.y + menuBox.height) + 16,
+    );
+    await page.screenshot({
+      path: SCREENSHOT_PATH,
+      clip: {
+        x: Math.floor(x),
+        y: Math.floor(y),
+        width: Math.ceil(right - x),
+        height: Math.ceil(bottom - y),
+      },
+    });
+  });
+});

desktop/tests/helpers/bridge.ts

@@ -159,6 +159,11 @@ type MockInstallRuntimeResult = {
 };
 
 type MockBridgeOptions = {
+  ttsSettings?: {
+    version: number;
+    agentTextToSpeech: boolean;
+    voicePreferences: string[];
+  };
   /** Advertised HEAD for the first mock project without adding that branch. */
   projectHeadBranch?: string;
   /** Relay NIP-11 identity used to sign authoritative repository state. */

desktop/tests/helpers/settings.ts

@@ -3,6 +3,7 @@ import { expect, type Page } from "@playwright/test";
 type SettingsSection =
   | "profile"
   | "notifications"
+  | "voice"
   | "agents"
   | "channel-templates"
   | "compute"