feat: add prek pre-commit hooks and dependabot (#1720)

* feat: add prek pre-commit hooks and dependabot

Pre-commit hooks (via prek):
- Basic hygiene: trailing-whitespace, end-of-file-fixer, check-yaml, check-added-large-files, check-merge-conflict
- Security: detect-secrets, zizmor (GitHub Actions audit)
- Linting: shellcheck, actionlint, oxlint, swiftlint
- Formatting: oxfmt, swiftformat

Dependabot:
- npm and GitHub Actions ecosystems
- Grouped updates (production/development/actions)
- 7-day cooldown for supply chain protection

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* docs: add prek install instruction to AGENTS.md

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

.pre-commit-config.yaml

@@ -0,0 +1,85 @@
+# Pre-commit hooks for clawdbot
+# Install: prek install
+# Run manually: prek run --all-files
+#
+# See https://pre-commit.com for more information
+
+repos:
+  # Basic file hygiene
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v6.0.0
+    hooks:
+      - id: trailing-whitespace
+        exclude: '^(docs/|dist/|vendor/|.*\.snap$)'
+      - id: end-of-file-fixer
+        exclude: '^(docs/|dist/|vendor/|.*\.snap$)'
+      - id: check-yaml
+        args: [--allow-multiple-documents]
+      - id: check-added-large-files
+        args: [--maxkb=500]
+      - id: check-merge-conflict
+
+  # Secret detection (same as CI)
+  - repo: https://github.com/Yelp/detect-secrets
+    rev: v1.5.0
+    hooks:
+      - id: detect-secrets
+        args: [--baseline, .secrets.baseline]
+
+  # Shell script linting
+  - repo: https://github.com/koalaman/shellcheck-precommit
+    rev: v0.11.0
+    hooks:
+      - id: shellcheck
+        args: [--severity=error]  # Only fail on errors, not warnings/info
+        # Exclude vendor and scripts with embedded code or known issues
+        exclude: '^(vendor/|scripts/e2e/)'
+
+  # GitHub Actions linting
+  - repo: https://github.com/rhysd/actionlint
+    rev: v1.7.10
+    hooks:
+      - id: actionlint
+
+  # GitHub Actions security audit
+  - repo: https://github.com/zizmorcore/zizmor-pre-commit
+    rev: v1.22.0
+    hooks:
+      - id: zizmor
+        args: [--persona=regular, --min-severity=medium, --min-confidence=medium]
+        exclude: '^(vendor/|Swabble/)'
+
+  # Project checks (same commands as CI)
+  - repo: local
+    hooks:
+      # oxlint --type-aware src test
+      - id: oxlint
+        name: oxlint
+        entry: npx oxlint --type-aware src test
+        language: system
+        pass_filenames: false
+        types_or: [javascript, jsx, ts, tsx]
+
+      # oxfmt --check src test
+      - id: oxfmt
+        name: oxfmt
+        entry: npx oxfmt --check src test
+        language: system
+        pass_filenames: false
+        types_or: [javascript, jsx, ts, tsx]
+
+      # swiftlint (same as CI)
+      - id: swiftlint
+        name: swiftlint
+        entry: swiftlint --config .swiftlint.yml
+        language: system
+        pass_filenames: false
+        types: [swift]
+
+      # swiftformat --lint (same as CI)
+      - id: swiftformat
+        name: swiftformat
+        entry: swiftformat --lint apps/macos/Sources --config .swiftformat
+        language: system
+        pass_filenames: false
+        types: [swift]