v2.2-paseo-providers: Paseo provider stack + v2.2.1 pane-scoped chat fixes

Ship Paseo-equivalent provider snapshot, AgentComposerBar, ACP dispatch
rewrite with streaming/persist, permission prompts, and agent commands.
Follow-up: pane-scoped chat resolution, CoderMessageList tool timeline,
WS user-delta replace, and inference orphan tool_call stripping.
Archive openspec v2-2; update CHANGELOG and CURRENT.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/coder/src/services/provider-registry.ts

@@ -2,10 +2,21 @@ export interface ProviderDef {
   name: string;
   label: string;
   transport: 'native' | 'acp' | 'pty';
-  modelSource: 'llama-swap' | 'static';
+  modelSource: 'llama-swap' | 'static' | 'probe';
   staticModels?: Array<{ id: string; label: string }>;
+  /** Merge llama-swap models into probed list (OpenCode). */
+  mergeLlamaSwap?: boolean;
 }
 
+/**
+ * Model discovery rules (see provider-snapshot.ts):
+ * - boocode: llama-swap only
+ * - opencode: ACP probe + mergeLlamaSwap (prefixed llama-swap/* ids)
+ * - qwen: ACP probe + merge ~/.qwen/settings.json; PTY fallback reads settings only
+ * - cursor: ACP probe + cursor-agent models CLI fallback
+ * - goose / copilot: ACP probe only
+ * - claude: static manifest models + thinking options
+ */
 export const PROVIDERS: ProviderDef[] = [
   {
     name: 'boocode',
@@ -13,17 +24,24 @@ export const PROVIDERS: ProviderDef[] = [
     transport: 'native',
     modelSource: 'llama-swap',
   },
+  {
+    name: 'cursor',
+    label: 'Cursor Agent',
+    transport: 'acp',
+    modelSource: 'probe',
+  },
   {
     name: 'opencode',
     label: 'OpenCode',
     transport: 'acp',
-    modelSource: 'llama-swap',
+    modelSource: 'probe',
+    mergeLlamaSwap: true,
   },
   {
     name: 'goose',
     label: 'Goose',
     transport: 'acp',
-    modelSource: 'llama-swap',
+    modelSource: 'probe',
   },
   {
     name: 'claude',
@@ -38,9 +56,18 @@ export const PROVIDERS: ProviderDef[] = [
   {
     name: 'qwen',
     label: 'Qwen Code',
-    transport: 'pty',
-    modelSource: 'static',
+    transport: 'acp',
+    modelSource: 'probe',
+  },
+  {
+    name: 'copilot',
+    label: 'GitHub Copilot',
+    transport: 'acp',
+    modelSource: 'probe',
   },
 ];
 
 export const PROVIDERS_BY_NAME = new Map(PROVIDERS.map((p) => [p.name, p]));
+
+/** External agents probed on host (excludes native boocode). */
+export const PROBED_AGENT_NAMES = PROVIDERS.filter((p) => p.name !== 'boocode').map((p) => p.name);