fix(repo): restore mise tools in e2e-matrix workflow

[FrozenPandaz]

Current Behavior

The inline mise_toml config in e2e-matrix.yml was overwriting the entire mise.toml file, causing rust, dotnet, bun, and java to NOT be installed by mise. This resulted in slow package installs as these tools were downloaded during pnpm install instead.

Expected Behavior

All tools from mise.toml (rust, dotnet, bun, java) should be installed by mise, with only the node version varying based on the matrix.

Solution

Use mise's template syntax to make node version configurable via NODE_VERSION env var while preserving all other tools from mise.toml:

node = "{{ env['NODE_VERSION'] | default(value='24') }}"

Then in the workflow, set the env var instead of overriding the entire config:

- name: Setup dev tools with mise
  uses: jdx/mise-action@v3
  env:
    NODE_VERSION: ${{ matrix.node_version }}

Related Issue(s)

Fixes slow install times in nightly e2e-matrix workflow after #33772.