ci: add docs workflow with PR metadata generation

Add conditional metadata generation for PRs that modify both docs and
source files. This fixes broken link checker reports when a PR adds a
new module and documents it simultaneously - previously the link checker
would fail because metadata files are only generated on push to main.

Changes:
- Add docs-orchestrator.yml workflow with:
  - detect-changes job to check if PR touches source paths
  - pr-metadata-regen job that generates metadata and uploads as artifact
  - link-check job that downloads metadata artifact when available
  - build-site job for VitePress site generation
  - deploy-aws and crowdin-upload jobs for push events
  - Prettier formatting step before auto-commit on push

- Add Prettier for markdown formatting:
  - Add prettier ^3.2.0 as devDependency in docs/package.json
  - Add docs/.prettierrc with prose-preserving config

- Remove normalize_whitespace from metadata_sync.sh (Prettier handles
  whitespace normalization now)

Signed-off-by: Ramon Roche <mrpollo@gmail.com>

docs/.prettierrc

@@ -0,0 +1,8 @@
+{
+  "proseWrap": "preserve",
+  "tabWidth": 2,
+  "useTabs": false,
+  "printWidth": 9999,
+  "endOfLine": "lf",
+  "embeddedLanguageFormatting": "off"
+}

docs/package.json

@@ -23,5 +23,8 @@
     "open-editor": "^5.0.0",
     "vitepress": "^1.6.3",
     "vue3-tabs-component": "^1.3.7"
+  },
+  "devDependencies": {
+    "prettier": "^3.2.0"
   }
 }