Add an install script for Linux (install-local.sh)

[jstuart0]

Goal

One-liner install for Linux users that pulls the AgentPulse docker image, starts the container with a data volume, and sets up hooks for Claude Code + Codex. Mirrors scripts/install-local.ps1 (Windows) but for POSIX shells.

Background

Existing files:

• scripts/setup.sh — installs hooks into an existing AgentPulse instance (assumes server already running).
• scripts/install-local.ps1 — full first-run Windows install (docker run + hook wire-up).

The Linux equivalent is missing, so Linux users have to stitch together docker + setup.sh by hand.

Scope

• scripts/install-local.sh — POSIX shell, no Bash-isms. Steps:
  1. Detect Docker (bail with a helpful install hint if missing).
  2. Pull or use the local agentpulse image (default ghcr.io/jstuart0/agentpulse:latest).
  3. Create a named volume (agentpulse-data) and bind-mount it at /app/data.
  4. Start the container with -e DISABLE_AUTH=true (safe default for local-only use).
  5. Wait for /api/v1/health to come up (polling with timeout).
  6. Invoke setup.sh pointed at the local instance.
• Serve at GET /install-local.sh the same way /setup.sh is served (see src/server/routes/setup.ts).

Acceptance criteria

• curl -sSL http://localhost:3000/install-local.sh | sh on a fresh Linux box installs docker + starts AgentPulse + wires hooks for the current user.
• Idempotent — running it twice doesn't leave two containers or duplicate hooks.
• README updated with the one-liner under "Install".