Switch to a shared xeus for the emscripten build

[anutosh491]

Description

The main motivation here is to enable support for jupyter widgets

The above would fail while using a static xeus build because the comm registry in xeus is a singleton and won't work well if we use a static build for xeus.

Type of change

Please tick all options which are relevant.

• Bug fix
• New feature
• Added/removed dependencies
• Required documentation updates

[anutosh491]

Hey @SylvainCorlay,

Now that jupyterlite-xeus 4.0.1 is out, if we have

    "shared": {
 +   "libxeus.so": "lib/libxeus.so",
      "libclangCppInterOp.so": "lib/libclangCppInterOp.so"
    }

We would get

(xeus-lite-host) anutosh491@Anutoshs-MacBook-Air build % jupyter lite build --XeusAddon.prefix=$PREFIX
static:jupyter-lite.json
.  pre_status:static:jupyter-lite.json
    tarball:         jupyterlite-app-0.6.0.tgz 15MB
    output:          /Users/anutosh491/work/xeus-cpp/build/_output
    lite dir:        /Users/anutosh491/work/xeus-cpp/build
    apps:            
    sourcemaps:      True
    unused packages: True
archive:archive
contents:contents
icons:icons
lite:jupyter-lite.json
mimetypes:jupyter-lite.json
serve:contents
settings:overrides
translation:translation
.  status:archive:archive
[LiteBuildApp] No archive (yet): build-jupyterlite.tgz
.  status:contents:contents
    contents: 0 files
.  status:icons:icons
    favicon files: 7 files
.  status:lite:jupyter-lite.json
[LiteBuildApp]     jupyter-lite.(json|ipynb): 0 files
.  status:mimetypes:jupyter-lite.json
    filetypes:         26 
.  status:serve:contents
    url: http://127.0.0.1:8000/
    server: tornado
    headers:
.  status:settings:overrides
    overrides.json: 0
.  status:translation:translation
    translation files: 2 files
static:output_dir
-- pre_init:static:output_dir
static:unpack
-- init:static:unpack
federated_extensions:copy:ext:jupyterlab_pygments
federated_extensions:copy:ext:@jupyterlite/xeus-extension
-- pre_build:federated_extensions:copy:ext:jupyterlab_pygments
-- pre_build:federated_extensions:copy:ext:@jupyterlite/xeus-extension
icons:copy
/Users/anutosh491/micromamba/envs/xeus-lite-host/lib/python3.13/site-packages/jupyterlite_core/addons/translation.py:89: UserWarning: [lite] [translation] install `jupyterlab_server` to load translations: No module named 'jupyterlab_server'
  if not self.is_sys_prefix_ignored() and has_optional_dependency(
translation:copy
.  build:icons:copy
-- build:translation:copy
federated_extensions:patch
federated_extensions:settings
jupyterlite-xeus:copy:xeus-cpp-wasm-host:xcpp23:logo-64x64.png
jupyterlite-xeus:copy:xeus-cpp-wasm-host:xcpp23:logo-32x32.png
jupyterlite-xeus:copy:xeus-cpp-wasm-host:xcpp23:logo-svg.svg
jupyterlite-xeus:copy:xeus-cpp-wasm-host:xcpp23:libxeus.so
jupyterlite-xeus:copy:xeus-cpp-wasm-host:xcpp23:libclangCppInterOp.so
jupyterlite-xeus:copy:xeus-cpp-wasm-host:xcpp23:libxeus.so
########################################
Execution aborted.
Task generation 'post_build' has duplicated definition of 'post_build:jupyterlite-xeus:copy:xeus-cpp-wasm-host:xcpp23:libxeus.so'

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.78%. Comparing base (c0d4edc) to head (72ee473).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #334   +/-   ##
=======================================
  Coverage   81.78%   81.78%           
=======================================
  Files          20       20           
  Lines         950      950           
  Branches       87       87           
=======================================
  Hits          777      777           
  Misses        173      173           

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[anutosh491]

Cc @SylvainCorlay this should be ready now !