feat: add fail-closed Local Delegation to Cairn (signals-dashboard 0.3.0) (#2666)

* feat: add fail-closed Local Delegation to Cairn dashboard

Port the-workshop Local Delegation seam into signals-dashboard 0.3.0.
Orthogonal off/on control beside repo/connected profiles; enable only when
local-agent-delegation is installed and a qualified route receipt is present.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: address Local Delegation review (skill path + README catalog)

- Walk marketplace/plugin and _direct install roots for local-agent-delegation
- Update plugins/signals-dashboard README and regenerate docs/README.plugins.md

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: keep Local Delegation Windows launches from reparsing -i prompt

Long LD orientation text split under wt/cmd on Windows (0x80070002). Keep
-i short/quote-free; rely on WORKSHOP_LOCAL_DELEGATION=enabled (+ skill)
for policy. Add charset/length guard tests.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: surface Local Delegation effective state on open toast and badge

Keep -i short with one optional ASCII line. Show operators
"Local Delegation effective · route <id>" on open and in the summary control.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: address Local Delegation GHCP review comments

- Cross-platform path.join in receipt fixture
- Atomic .local-delegation.json write (no symlink follow)
- Case-insensitive WORKSHOP_LOCAL_DELEGATION env clear
- Windows Terminal: set/clear env via cmd before agent
- aria-pressed on Local toggle

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: store Local Delegation preference user-locally, not in the workshop repo

A cloned workshop must not be able to ship preference:on. Key operator intent
under ~/.copilot/workshop-local-delegation/ by canonical workshop path.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: preserve path case in Local Delegation preference key

Lowercasing collided distinct workshops on case-sensitive filesystems.
Normalize separators only; realpath already supplies a stable path.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: allow parentheses in quoted Windows Local Delegation launches

Args are quote-wrapped; only block % and ! expanders inside quotes so paths
like C:\Work\Project (1) still launch.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

* fix: apply quoted-arg Windows safety guard in launch path

Complete the parentheses fix: use isSafeQuotedWindowsCmdArg for cmdSafe.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

---------

Co-authored-by: Jenny Ferries <jenny.ferries@microsoft.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Michael Recachinas <mrecachinas@github.com>
Copilot-Session: c39b7696-c854-40c2-b2d6-cce84ba09750

extensions/signals-dashboard/launch-profile.test.mjs

@@ -7,6 +7,7 @@ import { join } from "node:path";
 import {
     buildDeskAgentArgv,
     isDeskProfile,
+    isSafeQuotedWindowsCmdArg,
     isSafeWindowsCmdShim,
     isWindowsAppExecutionAlias,
     normalizeDeskProfile,
@@ -41,6 +42,10 @@ test("quotes trusted cmd shim arguments and rejects percent-bearing paths", () =
     assert.equal(quoteWindowsCmdArgument("--scope"), "\"--scope\"");
     assert.equal(isSafeWindowsCmdShim("C:\\Program Files\\Agency\\agency.cmd"), true);
     assert.equal(isSafeWindowsCmdShim("C:\\Users\\%USERNAME%\\agency.cmd"), false);
+    // Quoted args may contain parentheses (common workshop folders).
+    assert.equal(isSafeQuotedWindowsCmdArg("C:\\Work\\Project (1)"), true);
+    assert.equal(isSafeQuotedWindowsCmdArg("C:\\Users\\%USERNAME%\\w"), false);
+    assert.equal(isSafeQuotedWindowsCmdArg("C:\\Users\\!DELAY!\\w"), false);
 });
 
 test("executes a Windows cmd shim with safe quoting", {