Plugin: add binding review and bulk detach flows

[huntharo]

Problem

We need a way to review and manage all conversation bindings relevant to this plugin, including a bulk detach flow.

Examples:

• list what is currently bound
• detect stale local-vs-core mismatches
• support /codex_detach all

Current Findings

• The plugin's local store can list only the bindings it has persisted locally.
• The SDK surface exposed in this repo only gives us bind, unbind, and resolveByConversation; it does not give us a "list all current runtime bindings" API.
• OpenClaw core has richer binding helpers internally and also exposes CLI binding-management patterns elsewhere (openclaw agents bindings, openclaw agents unbind --all), but that capability is not surfaced to this plugin through the current runtime API shim.

Proposed Scope

• Add a plugin-visible binding review command or UI.
• Support bulk detach for plugin-owned bindings.
• Make the feature robust even if local plugin state was lost or became stale.
• Likely requires OpenClaw core/API additions so plugins can enumerate their current bindings instead of trusting only local cache/state.

Source Notes

• Plugin local binding list: src/state.ts:147
• Plugin SDK runtime binding surface: src/openclaw-plugin-sdk.d.ts:158
• OpenClaw conversation runtime exports listSessionBindingRecords etc.: /Users/huntharo/github/openclaw/src/plugin-sdk/conversation-runtime.ts:4
• OpenClaw binding record helper list operation: /Users/huntharo/github/openclaw/src/bindings/records.ts:25
• OpenClaw CLI binding management docs: /Users/huntharo/github/openclaw/docs/cli/agents.md:30