feat(skills): add neuledge-context skill for @neuledge/context MCP server

Adds a complete cross-cutting skill to install, configure, and manage
@neuledge/context — a local-first MCP server that delivers version-specific
library docs to AI agents via SQLite FTS5.

Includes:
- SKILL.md with 9-step process: install, global MCP registration, per-project
  --libs scoping, package management, auth, custom registry, upgrade, uninstall
- setup-neuledge-context.sh: pinned version install, idempotent version check
- secure-context-config.sh: chmod 600 on ~/.context/config.json after auth
- 13-case test suite covering both scripts (all pass)
- eval.yaml with 6 trigger tests and 4 output tests
- references/: context-cli-reference.md, http-mode.md, install-notes.md

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TP4EGbBg3XMcyF28Lx78XJ

scripts/secure-context-config.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Sets secure file permissions on ~/.context/config.json.
+# Run after every `context auth add` to protect stored credentials.
+# Safe to run when the file does not exist yet.
+
+CONFIG="${HOME}/.context/config.json"
+
+if [ ! -f "$CONFIG" ]; then
+  echo "Skipped: ${CONFIG} does not exist — no permissions to set."
+  exit 0
+fi
+
+chmod 600 "$CONFIG"
+echo "Secured: ${CONFIG} set to 600 (owner read/write only)."

scripts/setup-neuledge-context.sh

@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Installs @neuledge/context globally at a pinned version.
+# Usage: setup-neuledge-context.sh [VERSION]
+#   VERSION — npm version string (default: 1.2.0)
+# Idempotent: skips install if already at the target version.
+
+TARGET_VERSION="${1:-1.2.0}"
+
+current_version() {
+  context --version 2>/dev/null | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1 || echo ""
+}
+
+CURRENT="$(current_version)"
+
+if [ "$CURRENT" = "$TARGET_VERSION" ]; then
+  echo "Already at @neuledge/context@${TARGET_VERSION} — nothing to do."
+  exit 0
+fi
+
+if [ -n "$CURRENT" ]; then
+  echo "Upgrading @neuledge/context from ${CURRENT} to ${TARGET_VERSION}..."
+else
+  echo "Installing @neuledge/context@${TARGET_VERSION}..."
+fi
+
+npm install -g "@neuledge/context@${TARGET_VERSION}"
+
+INSTALLED="$(current_version)"
+if [ "$INSTALLED" = "$TARGET_VERSION" ]; then
+  echo "Done: @neuledge/context@${TARGET_VERSION} installed."
+else
+  echo "Error: expected version ${TARGET_VERSION} but got '${INSTALLED}'" >&2
+  exit 1
+fi