Cover the whole Consul CE HTTP API

[lyrixx]

This PR adds all the Consul Community Edition (v2.0.x) HTTP API endpoints to the SDK. It can be reviewed commit by commit.

New services

ACL, Config, Connect (CA + intentions), Coordinate, DiscoveryChain, Event, Operator (raft, keyring, autopilot, usage), Peering (+ exported / imported services), PreparedQuery, Snapshot and Status.

Existing services

• Agent, Catalog and Health now cover all their endpoints
• All documented options are whitelisted (blocking queries, consistency modes, filter, ...) in Agent, Catalog, Health, KV and Session
• Fix Agent::join() and Agent::forceLeave(): they sent GET, Consul only accepts PUT (405)

No BC break: nothing is removed nor renamed, only new optional arguments.

Client

• The ACL token is read from the CONSUL_HTTP_TOKEN environment variable (like the Consul CLI); an explicit X-Consul-Token header wins
• Multi-valued options are supported: ['tag' => ['v1', 'primary']] is sent as ?tag=v1&tag=primary (Symfony HttpClient would send ?tag[0]=v1&tag[1]=primary, which Consul does not understand)
• The dc option is allowed on all endpoints, except the ones local to the agent, the datacenter listings, and the catalog (de)registration (where it goes in the payload). A test checks every method forwards it.

Out of scope

• Enterprise-only endpoints and parameters (ns, partition, operator area / license / segment / audit / utilization, OIDC...)
• Deprecated endpoints (intentions by ID, POST /v1/connect/intentions)
• Streaming endpoints (/v1/agent/monitor, /v1/agent/metrics/stream)
• /v1/internal/*

Tests & tooling

• The CI Consul agent now runs with ACLs enabled (default_policy = allow, root management token)
• Integration tests against a real Consul 2.0 agent for almost every method; endpoints that can't run on a single dev agent, or would break it (leave, force-leave, raft, keyring, peering establish, ACL bootstrap), are tested with MockHttpClient
• PHPStan now runs against PHP 8.2 (the minimum supported version)
• README: services table, badges removed