feat: update the tailwind plugin to suuport tailwindv4 #2819 (#2903)

Inspired by #2819, #2829, and
https://github.com/pakornv/fresh-plugin-tailwindcss, I made minimal
modifications to the plugin-tailwind, I originally intended to update
based on #2829, but I was informed by the system that I couldn't push.

Due to the breaking changes in Tailwind v4, some PostCSS plugins are no
longer required. Additionally, I updated the syntax in the /www
directory. The /www directory now uses the updated plugin supported by
Tailwind v4.I think this has made initial progress.

# What This PR Solves
The Tailwind plugin has been updated to support Tailwind v4, and it is
currently functioning well both in the repository's www directory and in
the initialized project which for test.

## --patch-1

### 1. Dependency Optimization
- Removed `cssnano` dependency, using Tailwind v4's built-in
optimization(Based on @csvn 's suggestion)
- Removed `autoprefixer` dependency
- Updated `tailwind-plugin` version number
### 2. Build Configuration Adjustments
- Added `--node-modules-dir` parameter to `/www` task for Tailwind v4
support (Based on @marvinhagemeister 's suggestion)
- Added `--allow-scripts` parameter to enable `@tailwindcss/oxide`
execution
### 3. Code Adaptation
- Modified Tailwind-related code in `/www` to support Tailwind v4
- Updated dependency configuration in `deno.json`
### 4. Feature Restoration
- Added `imagescript` and `astral` dependencies to restore screenshot
functionality lost in previous PR updates
- Fixed the issue where the `tailwind-plugin` dependency was incorrectly
pointing to the JSR package instead of the local repository source code
in previous PR.

## --patch-2
- Upgraded Tailwind CSS to the latest version.
- Removed unnecessary dependencies.
- Enabled CSS minification by default when Fresh is in production mode.
- Updated docs/canary/examples/migration-guide.md to support the new
Tailwind plugin format.
- Updated init/src/init.ts to support the new Tailwind version and
plugin version, use new `@import "tailwindcss"`, and generate the new
plugin format.
- Updated init/src/init_test.ts: tests now expect `css` to match
`/tailwindcss/` instead of `/@tailwind/`.
- Removed plugin-tailwindcss/src/types.ts as it is no longer needed, and
updated plugin-tailwindcss/src/mod.ts and www/dev.ts to support the new
format.

Co-authored-by: Asher Gomez <ashersaupingomez@gmail.com>

## --patch-3
Addressing @marvinhagemeister feedback, this patch reverts the
unintended loss of PR #2960's changes caused by merge conflicts.

## --patch-4

I initialized a project according to the migration documentation and
used @fresh/update to test whether the plugin works properly with
v2-alpha-34. The results show that it works fine.

- The plugin is published at
jsr:@freshpress/fresh-plugin-tailwind@0.0.1-alpha.8.

- The test project is published at
https://github.com/SisyphusZheng/fresh-project-test/tree/main/fresh-project.

# How Testing Was Conducted

## Local Environment Testing
1. Environment Cleanup
```bash
rm -rf ./.cache/deno deno.lock node_modules
```

2. Test Execution
```bash
deno task www
```

3. Result Verification
- Checked functionality in local `/www` environment
- Confirmed all features working properly

## Code Inspection
- Passed `deno task ok` check

## This forked /www website is hosted and running on GitHub Codespaces,
with support for the latest code changes. You can check it out at:
https://silver-trout-pjr4jw7xx5x9299x6-8000.app.github.dev/

---------

Co-authored-by: 李嘉图·M·路 <146103794+Ricardo-M-Zheng@users.noreply.github.com>
Co-authored-by: deno-deploy[bot] <75045203+deno-deploy[bot]@users.noreply.github.com>
Co-authored-by: Asher Gomez <ashersaupingomez@gmail.com>
Co-authored-by: Marvin Hagemeister <marvin@deno.com>

Author: 4 people

deno.json

@@ -48,11 +48,11 @@
     "@std/uuid": "jsr:@std/uuid@^1.0.7",
     "fresh": "jsr:@fresh/core@^2.0.0-alpha.29",
     "preact": "npm:preact@^10.26.6",
+    "@preact/signals": "npm:@preact/signals@^2.0.4",
     "preact-render-to-string": "npm:preact-render-to-string@^6.5.11",
     "$ga4": "https://raw.githubusercontent.com/denoland/ga4/main/mod.ts",
     "@luca/esbuild-deno-loader": "jsr:@luca/esbuild-deno-loader@^0.11.0",
     "@opentelemetry/api": "npm:@opentelemetry/api@^1.9.0",
-    "@preact/signals": "npm:@preact/signals@^2.0.4",
     "esbuild": "npm:esbuild@0.25.4",
     "esbuild-wasm": "npm:esbuild-wasm@0.25.4",
     "@std/crypto": "jsr:@std/crypto@1",
@@ -66,27 +66,25 @@
     "@std/path": "jsr:@std/path@1",
     "@std/semver": "jsr:@std/semver@1",
     "@std/streams": "jsr:@std/streams@1",
-
     "@astral/astral": "jsr:@astral/astral@^0.5.3",
     "@marvinh-test/fresh-island": "jsr:@marvinh-test/fresh-island@^0.0.1",
     "linkedom": "npm:linkedom@^0.18.10",
     "@std/async": "jsr:@std/async@^1.0.13",
     "@std/expect": "jsr:@std/expect@^1.0.16",
     "@std/testing": "jsr:@std/testing@^1.0.12",
 
-    "autoprefixer": "npm:autoprefixer@10.4.17",
-    "cssnano": "npm:cssnano@6.0.3",
-    "postcss": "npm:postcss@8.4.35",
-    "tailwindcss": "npm:tailwindcss@^3.4.1",
-
+    "@tailwindcss/postcss": "npm:@tailwindcss/postcss@^4.1.7",
+    "@tailwindcss/oxide": "npm:@tailwindcss/oxide@^4.1.7",
+    "postcss": "npm:postcss@8.5.3",
+    "tailwindcss": "npm:tailwindcss@^4.1.7",
     "ts-morph": "npm:ts-morph@^25.0.1",
-
-    "@fresh/plugin-tailwind": "jsr:@fresh/plugin-tailwind@^0.0.1-alpha.7",
+    "@fresh/plugin-tailwind": "./plugin-tailwindcss/src/mod.ts",
     "@std/front-matter": "jsr:@std/front-matter@^1.0.5",
     "fresh/compat": "./src/compat/mod.ts",
     "fresh/dev": "./src/dev/mod.ts",
     "fresh/runtime": "./src/runtime/shared.ts",
     "github-slugger": "npm:github-slugger@^2.0.0",
+    "imagescript": "https://deno.land/x/imagescript@1.3.0/mod.ts",
     "marked": "npm:marked@^15.0.11",
     "marked-mangle": "npm:marked-mangle@^1.1.9",
     "prismjs": "npm:prismjs@^1.29.0"