feat: analytics parity — tool cost, date ranges, budgets, query explorer, replay, snapshots (v2.4.0)

Analytics parity phases 2–7 (docs/plans/analytics-parity/), built on
138e706 and ported onto v2.3.1:
- Cost by AI tool (?tool= on cost/analytics/stats/workflows, by_tool,
  Codex fast/priority and flex tiers, agenthub_cost_usd_total{tool,model})
- Date ranges (from/to) on cost/analytics/workflows; Analytics range select
  with Today / This week (Monday) / This month (1st) / 7d / 30d / 90d / All /
  Custom; workflow filters carried into workflow-stats.js (read worker)
- Budgets and cost alerts as alert rule types (alert_rules rebuilt without
  its rule_type CHECK), GET /api/budgets/status, rule preview, spend pace,
  status-bar budget chip; rules stay editable in place
- Query Explorer (/query, allowlisted sort, CSV/JSON export) and scheduled
  reports (report_definitions/report_runs, Settings → Reports)
- Session Replay tab and immutable snapshots (session_snapshots, /snapshot/:token)
- Remote Codex sync, push ingest with a hashed token, privacy redaction and
  ignored folders (Settings → Data), Cursor sessions (no cost)
- Read-only MCP server, statusline, Grafana/Prometheus files

Also: resizable sidebar, pet run/wave animations, the workspace home keeps a
half-typed prompt, and the pre-commit hook runs only the related tests for a
small commit.

openapi.yaml

@@ -3,7 +3,7 @@
 openapi: 3.0.3
 info:
   title: Agent Dashboard for Claude Code API
-  version: 2.3.1
+  version: 2.4.0
   description: HTTP API for real-time Claude Code session monitoring, agent lifecycle tracking, analytics, pricing, hooks ingestion, and workflow intelligence.
   contact:
     name: Nguyễn Ngọc Trí Vĩ
@@ -230,7 +230,7 @@ components:
           format: date-time
         tool:
           type: string
-          description: 'The AI coding CLI that produced the session: `claude` (Claude Code''s hooks and imported transcripts), `codex` (Codex''s rollout journals and its opt-in hooks) or `antigravity` (agy''s conversation files and its opt-in hooks).'
+          description: 'The AI coding CLI that produced the session: `claude` (Claude Code''s hooks and imported transcripts), `codex` (Codex''s rollout journals and its opt-in hooks) `antigravity` (agy''s conversation files and its opt-in hooks) or `cursor` (Cursor''s agent transcripts — sessions only, no tokens).'
         agent_count:
           type: integer
           nullable: true
@@ -4787,6 +4787,7 @@ paths:
               - claude
               - codex
               - antigravity
+              - cursor
           description: Only the sessions of one CLI. Applied before `limit`, so a busy Codex lane cannot push Claude sessions off a page.
           example: claude
         - name: awaiting