Add Claude pre-push hooks for clippy and doc checks (#134)

Adds a Claude Code hook that runs before every `git push`:
- cargo +nightly fmt --check
- cargo clippy with -D warnings
- RUSTDOCFLAGS="-D warnings" cargo doc

Clippy and doc warnings are hard failures that block the push.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: prestwich

.claude/hooks/pre-push.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Consume stdin (hook protocol)
+cat > /dev/null
+
+cd "$(dirname "$0")/../.."
+
+echo "Running pre-push checks..." >&2
+
+if ! cargo +nightly fmt -- --check 2>&1; then
+    echo "Format check failed. Run 'cargo +nightly fmt' to fix." >&2
+    exit 2
+fi
+
+if ! cargo clippy --workspace --all-targets --all-features -- -D warnings 2>&1; then
+    echo "Clippy (--all-features) failed." >&2
+    exit 2
+fi
+
+if ! cargo clippy --workspace --all-targets --no-default-features -- -D warnings 2>&1; then
+    echo "Clippy (--no-default-features) failed." >&2
+    exit 2
+fi
+
+if ! RUSTDOCFLAGS="-D warnings" cargo doc --workspace --no-deps 2>&1; then
+    echo "Doc check failed." >&2
+    exit 2
+fi
+
+echo "All pre-push checks passed." >&2
+exit 0

.claude/settings.json

@@ -0,0 +1,17 @@
+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Bash",
+        "hooks": [
+          {
+            "type": "command",
+            "if": "Bash(git push *)",
+            "command": "\"$CLAUDE_PROJECT_DIR\"/.claude/hooks/pre-push.sh",
+            "timeout": 600
+          }
+        ]
+      }
+    ]
+  }
+}

CLAUDE.md

@@ -15,6 +15,18 @@ long-term maintenance and may receive active work.
 Pre-push: clippy (both feature sets where applicable) + fmt. Never use `cargo check/build`.
 These checks apply before any push — new commits, rebases, cherry-picks, etc.
 
+### Pre-push Checks (enforced by Claude hook)
+
+A Claude hook in `.claude/settings.json` runs `.claude/hooks/pre-push.sh`
+before every `git push`. The push is blocked if any check fails. The checks:
+
+- `cargo +nightly fmt -- --check`
+- `cargo clippy --workspace --all-targets --all-features -- -D warnings`
+- `cargo clippy --workspace --all-targets --no-default-features -- -D warnings`
+- `RUSTDOCFLAGS="-D warnings" cargo doc --workspace --no-deps`
+
+Clippy and doc warnings are hard failures.
+
 ## Style
 
 - Functional combinators over imperative control flow