chore(deps): upgrade Vite, Rolldown, and PostCSS

.github/workflows/upgrade-deps.yml

@@ -132,6 +132,17 @@ jobs:
             - Vitest is capped at the latest stable `5.x` release. Keep the exact
               version selected by the upgrade script when merging upstream catalogs.
               Official Vitest packages must use that version. Do not bypass the cap.
+            - Rolldown must use the same major.minor release line required by both
+              the pinned Vite and the installed tsdown. Read their original
+              `dependencies.rolldown` ranges from `vite/packages/vite/package.json`
+              and `packages/core/node_modules/tsdown/package.json`; the workspace
+              override can hide incompatible requirements. Select a published
+              Rolldown patch version that satisfies both ranges. Patch differences
+              are allowed; mixing `1.2.x` and `1.3.x` requirements is not.
+              If the latest releases require different Rolldown minor versions,
+              defer the incompatible upgrades and keep a compatible combination.
+              Keep `@tsdown/css` and `@tsdown/exe` at the selected tsdown version.
+              Do not add compatibility patches or overrides to bypass this rule.
             - Sync-remote tool: `pnpm tool sync-remote` (source in
               `packages/tools/src/sync-remote-deps.ts`) — clones rolldown/vite into the
               working tree, imports only their build roots and bundled packages,
@@ -157,7 +168,13 @@ jobs:
             - build-upstream action: ${{ steps.build-upstream.outcome }}
 
             ### Fixups to perform (in order)
-            1. If the `Upgrade dependencies and sync upstream` outcome above is `failure`,
+            1. Check the Rolldown compatibility policy even if the earlier steps succeeded.
+               Run `node packages/tools/src/check-rolldown-compat.ts` to check the
+               pinned version against the original Vite and tsdown requirements.
+               Correct incompatible version selections before other fixes. Keep the
+               upstream branch and commit, catalog, lockfiles, bundled versions,
+               and upgrade metadata consistent with the selected versions.
+               If the `Upgrade dependencies and sync upstream` outcome above is `failure`,
                fix it FIRST — nothing else will work until the merged workspace is correct.
                Read the failed command in the upgrade log and re-run it. Resolve
                catalog conflicts against the pinned Rolldown and Vite sources.
@@ -167,6 +184,9 @@ jobs:
                upgrade operations: `pnpm dedupe`,
                `node .github/scripts/upgrade-deps.ts --sync-bundled-deps`, then
                `pnpm install --no-frozen-lockfile` before building or testing.
+               Check the original Vite and tsdown Rolldown requirements again after
+               synchronization and deduplication; successful installation is not proof
+               of compatibility because Rolldown resolves through a workspace override.
             2. Reuse successful outputs from `./.github/actions/build-upstream/action.yml`.
                If the action failed, fix the failure and complete its remaining build commands.
                Rebuild affected packages after source or dependency changes. Preserve the
@@ -305,6 +325,7 @@ jobs:
           RELEASE_BUILD: 'true'
         run: |
           set -euo pipefail
+          node packages/tools/src/check-rolldown-compat.ts
           pnpm bootstrap-cli
           export PATH="$HOME/.vite-plus/bin:$PATH"
           pnpm test:unit

Cargo.toml

@@ -219,7 +219,7 @@ jsonschema = { version = "0.60.0", default-features = false }
 junction = "2.0.0"
 libtest-mimic = "0.8.2"
 memchr = "2.8.2"
-mimalloc-safe = "0.1.64"
+mimalloc-safe = "0.1.70"
 mime = "0.3.17"
 napi = { version = "3.12.2", default-features = false, features = [
   "async",