build: Update dependencies and pre-commit hooks

Bump mypy to 2.3.1 and refresh all pre-commit hooks (ruff 0.16,
markdownlint 0.18). Fix issues surfaced by the new tooling:

- Use lowercase samesite cookie values (mypy 2.x)
- Remove no-op global declarations and address new ruff findings;
  ignore rules that would require behavior changes
- Add missing comma in AI system prompt (strings were concatenated)
- Wrap long README lines for MD013

.pre-commit-config.yaml

@@ -15,7 +15,7 @@ repos:
       - id: detect-private-key
   - repo: https://github.com/astral-sh/ruff-pre-commit
     # Ruff version.
-    rev: v0.12.9
+    rev: v0.16.7
     hooks:
       # Run the linter.
       - id: ruff
@@ -24,26 +24,26 @@ repos:
       - id: ruff-format
         args: [--diff, --target-version, py312]
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.17.1
+    rev: v2.3.1
     hooks:
       - id: mypy
         exclude: ^(docs/|example-plugin/)
         args: [--ignore-missing-imports]
         additional_dependencies: [types-requests, pypdf]
   - repo: https://github.com/adrienverge/yamllint.git
-    rev: v1.37.1
+    rev: v1.38.0
     hooks:
       - id: yamllint
         args: [--strict]
 
   - repo: https://github.com/markdownlint/markdownlint
-    rev: v0.13.0
+    rev: v0.18.1
     hooks:
       - id: markdownlint
         exclude: "^.github|(^docs/_sidebar\\.md$)"
 
   - repo: https://github.com/shellcheck-py/shellcheck-py
-    rev: v0.11.0.1
+    rev: v0.11.0.1-1
     hooks:
       - id: shellcheck
         args: ["--severity=error"]
@@ -51,12 +51,12 @@ repos:
         files: "\\.sh$"
 
   - repo: https://github.com/golangci/misspell
-    rev: v0.7.0
+    rev: v0.8.0
     hooks:
       - id: misspell
         args: ["-i", "charactor"]
   - repo: https://github.com/python-poetry/poetry
-    rev: "2.1.4"
+    rev: "2.4.1"
     hooks:
       - id: poetry-check
       - id: poetry-lock