fix(desktop): bundle runtime .mjs scripts into the server bundle

[aterrylu]

Problem

Claude Code's statusline doesn't apply in the desktop app (works on hosted). Root cause: two .mjs files are loaded by path at runtime, not by import, so bun build --target=node never includes them and build-binary.ts never copied them:

1. providers/statusline.mjs — injected into every spawned session's --settings statusLine.command. In the bundled server the path resolves inside app Resources where the file doesn't exist; CC swallows the statusline error → no statusline, zero symptoms.
2. channel-server/dist.mjs — the per-agent MCP channel-server subprocess. Same latent bug: in the desktop, spawned agents' send/create_agent MCP tools would be dead. Worse, runtime.ts resolved it as ../channel-server/dist.mjs, which escapes the bundle dir entirely once bundled.

Same bug class as the spawn-helper fix already in build-binary.ts. This was a false-pass: embedded-mode-integration.test.ts explicitly sets statusLine: {enabled: false}, so nothing covered it.

Solution

flowchart LR
    subgraph src ["tsx from source"]
        SP1["scriptPaths.ts<br/>import.meta.dirname = src/"] --> A1["src/providers/statusline.mjs"]
        SP1 --> B1["src/channel-server/dist.mjs"]
    end
    subgraph bundle ["bun bundle (desktop)"]
        SP2["index.js (all modules concatenated)<br/>import.meta.dirname = bundle dir"] --> A2["bundle/providers/statusline.mjs"]
        SP2 --> B2["bundle/channel-server/dist.mjs"]
    end
    BB["build-binary.ts<br/>stageRuntimeScripts()"] -- "copies RUNTIME_SCRIPTS<br/>+ writes manifest" --> A2
    BB --> B2
    SMOKE["smoke-test-bundle.sh"] -- "fails if any manifest<br/>entry missing" --> bundle

Loading

• src/scriptPaths.ts (new) — single source of truth. import.meta.dirname is src/ from source and the bundle dir when bundled (bun concatenates every module into index.js), so the same relative paths work in both contexts. All three call sites (claude-code.ts, runtime.ts, run.ts) now import from it.
• build-binary.ts — stageRuntimeScripts() copies each RUNTIME_SCRIPTS entry into the bundle preserving relative paths, aborts the build (exit 1) on a missing source, and writes runtime-scripts.manifest.
• smoke-test-bundle.sh — loops over the manifest and fails on any missing script (or a missing/empty manifest), so the bundle-side check tracks the staging list automatically.
• run.ts — boot-time warning when a runtime script is missing (mirrors the gemini-cli existsSync precedent; CC otherwise swallows the failure silently in the field).
• script-paths.test.ts (new) — staging contract: RUNTIME_SCRIPTS ↔ source tree sync; exported script constants are auto-derived from the module's exports so a forgotten third constant fails the test; the --settings statusLine.command points at an existing file; statusLine.enabled: false still suppresses injection.

Testing

• make check green: 409 server + 209 dashboard tests (4 new)
• Bundle rebuilt; both scripts land at the resolved paths; full smoke test passes including new assertions
• import.meta.dirname semantics in bun --target=node bundles verified empirically (survives verbatim; Node populates it with the bundle dir)
• Staged statusline.mjs executed standalone from its bundle location — full two-line render with live hierarchy enrichment
• Negative tests: removed staged script → smoke FAILs + server logs [startup] warning; emptied manifest → smoke FAILs; removed source script → build aborts exit 1

Risks

• Low. Source-mode behavior is unchanged (same resolved paths, now via one module). Bundle layout mirrors the src/ tree shape.
• pr-artifact.yml's DMG build + headless smoke test is the end-to-end gate for the desktop artifact.

Alternatives considered

• Flat-copying statusline.mjs next to index.js and keeping per-file literals: rejected — no single literal works for runtime.ts in both contexts (../channel-server/ is correct from src/agents/ but escapes the bundle dir when bundled).
• Deriving the smoke-test list by grepping scriptPaths.ts: rejected in favor of a build-written manifest — the manifest asserts what the build actually intended to stage and works without repo source.

🤖 Generated with Claude Code

[nox-0x]

Approving — clean fix for a real silent failure, with the right shape: one source-of-truth module for runtime script paths, build-time staging that aborts on missing source, manifest-driven smoke check, and a boot-time warning. Test coverage matches the failure modes (source-tree sync, exports↔staging coverage, settings.statusLine command path), and the bundle side is covered by the existing smoke-test extension.

The load-bearing claim — import.meta.dirname surviving bun --target=node bundling and resolving to the bundle dir at runtime — is already proven in tree by the embedded-dashboard resolution in run.ts:170-171, so the contract is internally consistent.

One minor follow-up (not blocking): the comment block in stageNodePtySpawnHelper (build-binary.ts) still says "import.meta.dirname is NOT populated in a bun --target=node bundle", which contradicts both run.ts and this PR's design. Worth a one-line cleanup so future readers don't get conflicting guidance.