fix(vite): remove noExternal: true from service environment build

[hi-ogawa]

🔗 Linked issue

I think this can be removed from each service build since final nitro environment has noExternal: true, which can take care bundling up dependencies. Currently it's causing a large intermediate build for each service, for example in Vue Router SSR demo nitrojs/vite-examples#5, the build log shows a following:

◐ Building [Client]                                                                                                                                                                                                      ...
...
✓ built in 416ms

◐ Building [SSR]                                                                                                                                                                                                         
...
...
.nitro/vite/services/ssr/assets/parser-DCdUCwrd.js                        15.00 kB
.nitro/vite/services/ssr/entry-server.js                               1,438.92 kB  👈👈 all dependencies are bundled at this stage
✓ built in 992ms 👈👈

◐ Building [Nitro] (preset: node-server, compatibility: 2025-10-18)                                                                                                                                                      ...
...
.output/server/index.mjs                                               75.11 kB
.output/server/chunks/build/entry-server.mjs                        1,407.94 kB 👈👈 then mostly copied to here
✓ built in 1.89s 👈👈

After removing noExternal: true from each service (by locally patching), the build becomes:

◐ Building [Client]                                                                                                                                                                                                      ...
...
✓ built in 414ms

◐ Building [SSR]                                                                                                                                                                                                         ...
...
.nitro/vite/services/ssr/assets/app-Bm8psYAt.js                        1.86 kB
.nitro/vite/services/ssr/entry-server.js                               3.23 kB 👈👈
✓ built in 44ms 👈👈

◐ Building [Nitro] (preset: node-server, compatibility: 2025-10-18)                                                                                                                                                      ...
...
.output/server/chunks/build/entry-server.mjs                         5.46 kB
.output/server/index.mjs                                            75.11 kB 👈👈
✓ built in 1.05s 👈👈

With this, the build got faster and external tracing of nitro environment properly isolated runtime dependencies .output/server/node_modules, so .output becomes standalone output.

❓ Type of change

• 📖 Documentation (updates to the documentation, readme, or JSdoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

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commit: 66d35c2

[pi0]

Looks good @hi-ogawa. Any reason still kept in draft? / also wondering should we enable externals by default for other services?

[hi-ogawa]

Oh, I just forgot to undraft.

also wondering should we enable externals by default for other services?

What do you mean? After this change, the build behavior seems good to me. Ssr environment build leaves external as is (users or framework can still specify noExternal for their framework level package) and nitro environment build can take care external tracing to make final .output self-contained.