FN-6763: add themed workflow status switcher

Add a reusable dashboard workflow picker that shows inline task status counts across board and list views.

- Replace native workflow selects with a themed accessible dropdown component.
- Share workflow status count calculation between board and list views.
- Add styling, i18n labels, tests, and dashboard docs for the switcher behavior.

Files changed:
 docs/dashboard-guide.md                            |   3 +-
 packages/dashboard/app/components/Board.tsx        |  28 +--
 packages/dashboard/app/components/Lane.css         |   2 +
 .../dashboard/app/components/LeftSidebarNav.tsx    |   2 +-
 packages/dashboard/app/components/ListView.css     |  17 --
 packages/dashboard/app/components/ListView.tsx     |  31 ++-
 .../dashboard/app/components/WorkflowSwitcher.css  | 186 ++++++++++++++
 .../dashboard/app/components/WorkflowSwitcher.tsx  | 270 +++++++++++++++++++++
 .../app/components/__tests__/Board.test.tsx        |  60 +++--
 .../app/components/__tests__/ListView.test.tsx     |  79 +++++-
 .../components/__tests__/WorkflowSwitcher.test.tsx |  92 +++++++
 .../__tests__/workflowStatusCounts.test.ts         | 122 ++++++++++
 .../app/components/workflowStatusCounts.ts         |  54 +++++
 packages/i18n/locales/en/app.json                  |   9 +
 packages/i18n/locales/es/app.json                  |   9 +
 packages/i18n/locales/fr/app.json                  |   9 +
 packages/i18n/locales/ko/app.json                  |   9 +
 packages/i18n/locales/zh-CN/app.json               |   9 +
 packages/i18n/locales/zh-TW/app.json               |   9 +
 19 files changed, 930 insertions(+), 70 deletions(-)

Fusion-Task-Id: FN-6763
Fusion-Task-Lineage: 3503ea85-841a-4cd3-9960-1b22ef2cd4ea

docs/dashboard-guide.md

@@ -77,6 +77,7 @@ Features:
 - Task card header meta badges group priority, fast mode, agent-created provenance, and elapsed/created-time chips into one wrapping row; agent labels prefer `sourceMetadata.agentName` over raw agent IDs
 - Column ordering semantics: `todo` mirrors scheduler pickup order (priority descending, then oldest `createdAt`, then task ID); `triage`, `in-progress`, `in-review`, and `archived` remain priority-first with task-ID tie-breaks; `done` is ordered by most recent completion first (`columnMovedAt`, then `updatedAt`, then `createdAt` fallback)
 - On mobile, both default and workflow-mode boards fill the project viewport while the column strip remains the internal horizontal scroller with contained edge overscroll.
+- Board and List workflow switchers use a themed dropdown instead of a native select. The closed trigger and each workflow option show compact Todo / In Progress / Done counts derived from workflow column flags, excluding archived columns.
 
 ![Board view](./screenshots/dashboard-overview.png)
 
@@ -126,7 +127,7 @@ The workflow editor opens as a full-screen modal editor for inspecting built-ins
 
 Navigation:
 - Open a task or board surface that shows the workflow selector, then choose **Manage…**.
-- From the board workflow toolbar, use the edit workflow button beside the selector to open the currently selected workflow directly when one is selected.
+- From the board workflow toolbar, use the edit workflow button beside the selector to open the currently selected workflow directly when one is selected. The board/list workflow dropdown also previews each workflow's Todo / In Progress / Done task counts inline before switching.
 - Use the global **Workflow** / **Workflows** entry point from desktop header, compact header overflow, or mobile **More** navigation to browse definitions.
 - From Settings moved-setting stubs, choose **Open workflow settings** to jump to the default workflow's settings values.