Bump deps (#515)

* chore: add nix flake for reproducible dev environment

Signed-off-by: Sped0n <hi@sped0n.com>

* refactor: migrate SCSS to modern Sass (@use/@forward)

Update mixins to use Sass module functions (map.has-key/get).
Configure Vite for modern Sass API.
Introduce _foundation.scss for forwarding core modules.

Signed-off-by: Sped0n <hi@sped0n.com>

* fix: replace deprecated _build with build in frontmatter

Signed-off-by: Sped0n <hi@sped0n.com>

* chore: add vcache.sh script for vercel build cache management

Signed-off-by: Sped0n <hi@sped0n.com>

* refactor: migrate to ESLint v9 flat config

Remove legacy .eslintrc.json, .eslintignore, and .prettierrc.json.

Add eslint.config.mjs with love, prettier, solid, and import rules.

Update devDependencies (eslint@9, @typescript-eslint@8, etc.) and scripts.

Minor TS fixes: remove eslint-disable, add error logging, simplify conditional.

Signed-off-by: Sped0n <hi@sped0n.com>

* chore: replace vcache.sh with vercel.sh for Vercel build process

Delete vcache.sh script.

Add vercel.sh: install Dart Sass v1.93.3, copy generated assets between
node_modules and project dirs, run vite:build + hugo build, then copy back.

Signed-off-by: Sped0n <hi@sped0n.com>

* chore: setup dart-sass and split build steps in GitHub workflow

Signed-off-by: Sped0n <hi@sped0n.com>

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Signed-off-by: Sped0n <hi@sped0n.com>

layouts/partials/head/link.html

@@ -3,7 +3,7 @@
 
 {{/* critical style */}}
 {{- $style := dict "Source" "scss/critical.scss" "Fingerprint" $fingerprint -}}
-{{- $options := dict "enableSourceMap" true "includePaths" (slice "node_modules") -}}
+{{- $options := dict "enableSourceMap" true "includePaths" (slice "node_modules") "transpiler" "dartsass" -}}
 {{- $style = dict "Context" . "ToCSS" $options "Inline" true | merge $style -}}
 {{- partial "plugin/style.html" $style -}}