feat(desktop): add Cybara ACP harness preset

[metaspartan]

Summary

• add Cybara as a PATH-discovered tier-2 harness that launches cybara acp
• bundle the MIT-licensed Cybara mark with source and license provenance
• extract the preset catalog into a focused module so discovery stays below the file-size ratchet
• extend the backend/frontend logo contract coverage for the new preset

Related issue

Fixes #3445

No duplicate issue or pull request was found before filing the issue and starting implementation. No agent-config rules changed.

Testing

• cargo fmt --all -- --check
• cargo metadata --manifest-path desktop/src-tauri/Cargo.toml --no-deps --format-version 1
• node --import ./test-loader.mjs --experimental-strip-types --test src/features/onboarding/ui/presetLogos.test.mjs (12 passed)
• pnpm typecheck
• pnpm check
• packaged Cybara v1.0.1833 ACP initialize + session/new handshake using Buzz protocol-v2 capabilities and prompt fields; negotiated v1, returned a session ID, kept stdout JSON-RPC-only, and shut down cleanly
• bun test tests/core/acp.test.ts in Cybara (16 passed)

The full Rust/Tauri compile could not be run locally because the checkout volume had about 1 GiB free after cleaning generated Cargo output; GitHub CI is the authoritative full-build run.