feat(plugins): make CCAM installable straight from a Claude Code plugin

Adds a root `ccam` plugin (`.claude-plugin/plugin.json`, `"source": "./"`) so
`/plugin marketplace add` + `/plugin install ccam@...` is enough on a machine
with nothing but Claude Code: no clone, no npm run setup, no manual npm start.

- scripts/plugin-bootstrap.js: SessionStart hook. Fast-path exit, Node >=22.5
  gate (node:sqlite), mkdir lock with stale reclaim, deps installed into
  ~/.claude/agent-dashboard/runtime/ (never the plugin cache), legacy
  checkout-hook cleanup (backed up), ~/.local/bin/ccam launcher, eager UI
  build so client routes like /run work immediately, detached server spawn.
- scripts/plugin-open.js, scripts/plugin-doctor.js: /ccam-open, /ccam-doctor.
- server/index.js: DASHBOARD_CLIENT_DIST override (plugin cache is read-only).
- mcp/build/ is committed (plugin MCP servers start before any bootstrap could
  build them) and kept honest by scripts/check-mcp-build.js (content hash,
  not mtime), enforced by pre-commit when mcp/src changes.
- plugins/ccam-dashboard/.mcp.json moved under plugins/ccam/ with a working
  ${CLAUDE_PLUGIN_ROOT} path (the old relative path never resolved from a
  marketplace-cached subdir).
- Docs: README, INSTALL, SETUP, ARCHITECTURE, CLAUDE.md, docs/PLUGINS.md,
  docs/MCP.md, docs/CLI.md, docs/HOOKS.md.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

.claude-plugin/marketplace.json

@@ -1,6 +1,6 @@
 {
   "name": "claude-code-agent-monitor-plugins",
-  "description": "Official plugin marketplace for Claude Code Agent Monitor — 10 plugins for analytics, cost guardrails, productivity, developer tools, AI insights, session forensics, workflow/fleet intelligence, reliability/SLOs, config & memory governance, and dashboard connectivity. Every plugin is powered by the local Agent Monitor API.",
+  "description": "Official plugin marketplace for Claude Code Agent Monitor — the `ccam` plugin installs the dashboard itself (hooks, server, CLI, MCP), plus 10 focused plugins for analytics, cost guardrails, productivity, developer tools, AI insights, session forensics, workflow/fleet intelligence, reliability/SLOs, config & memory governance, and dashboard connectivity. Every plugin is powered by the local Agent Monitor API.",
   "owner": {
     "name": "smartgift",
     "url": "https://git.smartgift.io.vn/Smartgift-AI"
@@ -8,6 +8,12 @@
   "homepage": "https://git.smartgift.io.vn/Smartgift-AI/Claude-Code-Monitor",
   "repository": "https://git.smartgift.io.vn/Smartgift-AI/Claude-Code-Monitor",
   "plugins": [
+    {
+      "name": "ccam",
+      "source": "./",
+      "description": "The dashboard itself. Installs the Claude Code event hooks, boots the local server, puts the `ccam` CLI on PATH and connects the MCP tools — no checkout and no `npm run setup`. Install this one first; the ten focused plugins below all read from the API it provides.",
+      "tags": ["dashboard", "monitoring", "hooks", "mcp", "cli"]
+    },
     {
       "name": "ccam-analytics",
       "path": "plugins/ccam-analytics",