fix: make requester bridge work on OpenClaw 2026.5

[COOLBGT]

Summary

• register the plugin on the real cloudsigma provider path used by OpenClaw 2026.5.x while retaining staging/legacy aliases
• send requester-local /tools/invoke calls using OpenClaw's expected { name, arguments } shape, while retaining legacy { tool, args } fields for compatibility
• fall back to the requester host's local openclaw.json gateway token so a systemd TAAS_REQUESTER_LOCAL_GATEWAY_TOKEN drop-in is not required for standard installs
• raise requester bridge HTTP timeout from 1.2s to 10s and unref background timers so tests/CLI imports exit cleanly
• bump package version to 0.5.2

Why

Live E2E testing on OpenClaw 2026.5.7 showed the plugin loaded but did not attach to the real CloudSigma request path with the old provider id/aliases. After that was fixed, requester bridge tool execution reached the local Gateway but failed unless the Gateway token was manually injected into the service environment. The plugin should discover the local requester Gateway token from the existing OpenClaw config by default, with env vars kept as overrides.

Verification

• npm test
• npm run build
• Live blago-test E2E: requester bridge called session_status and returned 🦞 OpenClaw 2026.5.7 (eeef486) with local_tool_ok=1, bridge_outcome_ok=1, abort_count=0, unauth_count=0
• Live dev-milen E2E: direct /tools/invoke returned ok=true; agent requester bridge test returned 🦞 OpenClaw 2026.5.7 (eeef486)