feat(cli): TUI full-screen attach to cli-agent sessions (U14)

Suspend-and-handoff passthrough from the Ink TUI to a cli-agent PTY session:
mint an attach ticket, open the cli-session WebSocket, enter the alternate
screen + raw mode, stream WS scrollback/data frames to stdout, frame stdin
bytes into input messages, propagate resizes, and ACK consumed bytes for flow
control. Detach chord Ctrl-] restores the terminal and remounts Ink; a dropped
WS surfaces the error and restores the terminal cleanly.

Untrusted terminal output is neutralized through the same hardening filter the
dashboard WS bridge uses (re-exported from @fusion/dashboard) so OSC 52, non-
http(s) OSC 8 links, and device-status queries are stripped before reaching the
host TTY — the riskiest leg, since the host terminal honors more sequences than
xterm.js. CJK/double-width bytes pass through verbatim.

- packages/cli/src/commands/dashboard-tui/terminal-attach.ts (passthrough loop +
  injectable WS transport for tests)
- controller.openTerminalAttach() Ink integration (unmount/run/remount)
- adds `ws` runtime dep to packages/cli
- re-exports neutralizeTerminalOutput/flushTerminalOutput from @fusion/dashboard

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/cli/package.json

@@ -68,7 +68,8 @@
     "multer": "^2.1.1",
     "node-pty": "npm:@homebridge/node-pty-prebuilt-multiarch@^0.13.1",
     "react": "^19.2.0",
-    "react-i18next": "^17.0.8"
+    "react-i18next": "^17.0.8",
+    "ws": "^8.18.0"
   },
   "peerDependencies": {
     "@earendil-works/pi-ai": "*",
@@ -95,6 +96,7 @@
     "@fusion/pi-llama-cpp": "workspace:*",
     "@types/node": "^22.0.0",
     "@types/react": "^19.2.0",
+    "@types/ws": "^8.5.0",
     "@vitest/coverage-v8": "^3.1.0",
     "cross-env": "^7.0.0",
     "esbuild": "^0.25.12",