Remove legacy Sphinx docs/ and finish the Mintlify cutover (#28964)

.pre-commit-config.yaml

@@ -37,7 +37,7 @@ repos:
         args:
           - --select=F401,F821,UP037
           - --fix
-        files: ^(benchmark/|docs/|examples/|python/sglang/|sgl-model-gateway/py_*|test/)
+        files: ^(benchmark/|docs_new/|examples/|python/sglang/|sgl-model-gateway/py_*|test/)
         exclude: |
           (?x)^(
           .*/__init__\.py$|
@@ -105,13 +105,6 @@ repos:
         language: system
         files: ^python/sglang/.*\.py$
         pass_filenames: false
-      - id: check-no-docs-changes
-        name: reject changes under legacy docs/
-        entry: python3 scripts/ci/check_no_docs_changes.py
-        language: system
-        pass_filenames: false
-        always_run: true
-        stages: [pre-commit]
       - id: rustfmt-sgl-model-gateway
         name: rustfmt sgl-model-gateway (nightly)
         entry: bash -c 'rustup component add --toolchain nightly rustfmt >/dev/null && cd sgl-model-gateway && cargo +nightly fmt -- --check'
@@ -124,6 +117,13 @@ repos:
         language: system
         files: ^experimental/sgl-router/.*\.rs$
         pass_filenames: false
+      - id: mint-broken-links
+        name: check docs_new links (Mintlify; opt-in, requires `mint` on PATH)
+        entry: bash -c 'cd docs_new && mint broken-links --check-anchors --check-redirects'
+        language: system
+        pass_filenames: false
+        always_run: true
+        stages: [manual]
   - repo: https://github.com/lycheeverse/lychee.git
     rev: lychee-v0.22.0
     hooks:
@@ -131,9 +131,7 @@ repos:
         name: check doc links (offline)
         args: ["--config", ".github/linters/lychee.toml"]
         stages: [manual]
-        exclude: ^docs/_build/
         files: |
           (?x)^(
-            README\.md|
-            docs/.*\.(md|rst|ipynb)
+            README\.md
           )$