fix(FN-2139): wire source export condition into CLI builds

- Add "source" export entries for @fusion/core, @fusion/dashboard, and @fusion/engine package exports
- Configure tsup/esbuild to include the "source" condition when resolving workspace dependencies
- Pass --conditions=source to bun compile so compiled CLI binaries resolve source-conditioned exports consistently

packages/cli/build.ts

@@ -243,6 +243,7 @@ function compileBinary(outFile: string, target: string, isCrossCompile: boolean)
       "--target",
       target,
       "--minify",
+      "--conditions=source",
     ],
     cwd: workspaceRoot,
     stdout: "inherit",