[HusnainMaroof]

Problem

Part of #96. Thanks @fadyehabamer for the measurements.

vite.config.ts asks for three shared chunks, but only shared-home is created. At 523 kB raw / 160 kB gzip it is the largest client chunk, and every page loads it.

Two causes:

1. Rolldown runs manualChunks as a single group with includeDependenciesRecursively: true. When HomeComponentRenderer / ProductsSlider go into shared-home, every module they import goes with them: the theme's product components, i18next, ky, sonner, TanStack Query, Swiper and the engine. Reordering the ifs does not help. Removing only the shared-home rule makes shared-product appear.
2. The shared-common matchers never match. @salla.sa/twilight-theme-engine ships prebuilt flat files (dist/Breadcrumb-7QGTM5S5.js, dist/chunk-*.js), so no module id contains /components/common/.

Fix

vite.config.ts only. The same intent moves to build.rolldownOptions.output.codeSplitting.groups, which supports priorities. This is the build's own hint.

• preload-helper, vendor-react, vendor-router and vendor-hooks keep their current matchers
• New vendor-core (i18next, ky, sonner, TanStack Query/Virtual) and vendor-swiper
• New vendor-salla: only the engine modules every page loads. The engine's lazy screens keep their own route chunks
• shared-common, shared-product and shared-home now each hold what their names say
• resolveDependencies is unchanged

Results

Client build, gzip -9, same script on both builds:

	master a913dfa	this PR
shared-home	160.4 kB	8.5 kB
Largest chunk	523 kB raw	265 kB raw, and the 500 kB warning is gone
shared-product / shared-common	not emitted	8.1 kB / 13.8 kB
Total client JS	425.4 kB	415.6 kB
JS per page at startup	344.5 kB	338.1 kB

Caching also improves: a theme-only change now invalidates small theme chunks instead of the 160 kB shared-home, and library chunks change only when a dependency is upgraded.

Size budget (#63)

I ran scripts/check-bundle.mjs with size-budget.json from feature/quality-gates-twig-parity-audit against both builds:

• master already exceeds the shared-home budget by 12.6 kB
• This PR is 23.7 kB under the total JS budget and 139 kB under the shared-home budget
• The five new chunks need budget entries (pnpm size:update). Their code moved there from other chunks; nothing was added
• vendor-react is 0.3 kB over its 5% margin, because React's own dependencies are now captured with it. Turning capture off for that group breaks the SSR build (preserveEntrySignatures: 'strict')

Not fixed here

Every page still loads the home blocks and Swiper, because app/router.tsx imports them statically. They are now small separate chunks rather than part of one 160 kB chunk. Making them lazy from the theme alone saved only about 4 kB more in my tests. The bigger win (up to 60 kB on cart, blog and account pages) needs engine changes:

• the engine package has no sideEffects field, so barrels pull in ProductPage / CartPage
• @salla.sa/twilight-theme-engine/skeleton (every route's pendingComponent) imports about 60 engine chunks
• route modules statically import the engine route objects for loader / head
• the route generator rewrites route files marked // @auto-generated on each build

Checks

• pnpm build passes (client and SSR), with no circular-chunk or execution-order warnings
• pnpm test: 606/606 pass
• pnpm typecheck passes
• Not tested against a live store in a browser (the demo store returns 422 "store not found")

Questions

1. Should this target master or feature/quality-gates-twig-parity-audit? That branch has the size budget and also changes vite.config.ts
2. Should I add the size-budget.json update to this PR?