add CCfW hooks (#22803)

Shamelessly lifted from uv.

Biggest win here is giving CCfW access to the `gh` CLI tool, which it
always otherwise tries and fails to use.

Author: carljm

.claude/hooks/session-start-web.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+set -euo pipefail
+
+# Install `gh`
+if ! command -v gh &> /dev/null; then
+    apt-get update -qq
+    apt-get install -y -qq gh
+fi
+
+# Install clippy and rustfmt for the active toolchain.
+rustup component add clippy rustfmt

.claude/hooks/session-start.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+set -euo pipefail
+
+# Dispatch to web hook if running remotely
+if [ "${CLAUDE_CODE_REMOTE:-}" = "true" ]; then
+  exec "$(dirname "$0")/session-start-web.sh"
+fi

.claude/settings.json

@@ -0,0 +1,15 @@
+{
+  "hooks": {
+    "SessionStart": [
+      {
+        "matcher": "startup",
+        "hooks": [
+          {
+            "type": "command",
+            "command": ".claude/hooks/session-start.sh"
+          }
+        ]
+      }
+    ]
+  }
+}