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>

---------

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

exampleSite/content/Erwitt/index.md

@@ -8,6 +8,6 @@ menu:
     identifier: Erwitt
     title: Erwitt
 unifiedAlt: '© Elliott Erwitt'
-_build:
+build:
   publishResources: false
 ---

exampleSite/content/Gruyaert/index.md

@@ -8,6 +8,6 @@ menu:
     identifier: Gruyaert
     title: Gruyaert
 unifiedAlt: '© Harry Gruyaert'
-_build:
+build:
   publishResources: false
 ---

exampleSite/content/Info/index.md

@@ -8,7 +8,7 @@ menu:
     identifier: Info
     title: Info
 unifiedAlt: ''
-_build:
+build:
   publishResources: false
 ---
 

exampleSite/content/Webb/index.md

@@ -8,6 +8,6 @@ menu:
     identifier: Webb
     title: Webb
 unifiedAlt: '© Alex Webb'
-_build:
+build:
   publishResources: false
 ---