Add debug log panel, centered modals, and fix multiple UX issues

Features:
  - Add /logs command to toggle debug log panel (20% width on right)
  - Debug panel shows API calls, streaming events, tool calls, state changes
  - Add /help submenus with detailed command explanations
  - Center all modal dialogs in the terminal window

  Bug Fixes:
  - Fix streaming content not displaying (add fallback when streaming fails)
  - Fix permission modal shortcut key mismatch ('a' → 'l' for local scope)
  - Fix agent prompt accumulation when switching agents multiple times
  - Fix permission modal using brittle index for "No" option

  Improvements:
  - Restrict git commands (add, commit, push, etc.) unless user explicitly requests
  - Unify permission options across all UI components
  - Add Ollama model selection when switching to Ollama provider
  - Store base system prompt to prevent agent prompt stacking

  New files:
  - src/tui-solid/components/debug-log-panel.tsx
  - src/tui-solid/components/centered-modal.tsx
  - src/tui-solid/components/help-menu.tsx
  - src/tui-solid/components/help-detail.tsx
  - src/constants/help-content.ts

src/commands/components/chat/commands/commandsRegistry.ts

@@ -1,6 +1,6 @@
 import { saveSession } from "@services/session";
-import { showHelp } from "@commands/components/chat/commands/show-help";
 import { clearConversation } from "@commands/components/chat/history/clear-conversation";
+import { appStore } from "@tui/index";
 import { showContextFiles } from "@commands/components/chat/context/show-context-files";
 import { removeFile } from "@commands/components/chat/context/remove-file";
 import { showContext } from "@commands/components/chat/history/show-context";
@@ -24,8 +24,8 @@ const COMMAND_REGISTRY: Map<string, CommandHandler> = new Map<
   string,
   CommandHandler
 >([
-  ["help", () => showHelp()],
-  ["h", () => showHelp()],
+  ["help", () => appStore.setMode("help_menu")],
+  ["h", () => appStore.setMode("help_menu")],
   ["clear", (ctx: CommandContext) => clearConversation(ctx.state)],
   ["c", (ctx: CommandContext) => clearConversation(ctx.state)],
   ["files", (ctx: CommandContext) => showContextFiles(ctx.state.contextFiles)],
@@ -106,6 +106,17 @@ const COMMAND_REGISTRY: Map<string, CommandHandler> = new Map<
     },
   ],
   ["mcp", async (ctx: CommandContext) => handleMCP(ctx.args)],
+  [
+    "logs",
+    () => {
+      appStore.toggleDebugLog();
+      const { debugLogVisible } = appStore.getState();
+      appStore.addLog({
+        type: "system",
+        content: `Debug logs panel ${debugLogVisible ? "enabled" : "disabled"}`,
+      });
+    },
+  ],
 ]);
 
 export default COMMAND_REGISTRY;

src/commands/components/execute/index.ts

@@ -26,6 +26,7 @@ import { agentLoader } from "@services/agent-loader";
 
 interface ExecuteContext {
   state: ChatServiceState | null;
+  baseSystemPrompt: string | null;
 }
 
 const createHandleExit = (): (() => void) => (): void => {
@@ -51,16 +52,22 @@ const createHandleAgentSelect =
     (ctx.state as ChatServiceState & { currentAgent?: string }).currentAgent =
       agentId;
 
-    if (agent.prompt) {
-      const basePrompt = ctx.state.systemPrompt;
-      ctx.state.systemPrompt = `${agent.prompt}\n\n${basePrompt}`;
+    // Use the stored base prompt to avoid accumulation when switching agents
+    const basePrompt = ctx.baseSystemPrompt ?? ctx.state.systemPrompt;
 
-      if (
-        ctx.state.messages.length > 0 &&
-        ctx.state.messages[0].role === "system"
-      ) {
-        ctx.state.messages[0].content = ctx.state.systemPrompt;
-      }
+    if (agent.prompt) {
+      ctx.state.systemPrompt = `${agent.prompt}\n\n${basePrompt}`;
+    } else {
+      // Reset to base prompt if agent has no custom prompt
+      ctx.state.systemPrompt = basePrompt;
+    }
+
+    // Update the system message in the conversation
+    if (
+      ctx.state.messages.length > 0 &&
+      ctx.state.messages[0].role === "system"
+    ) {
+      ctx.state.messages[0].content = ctx.state.systemPrompt;
     }
   };
 
@@ -81,6 +88,15 @@ const createHandleProviderSelect =
     const config = await getConfig();
     config.set("provider", providerId as "copilot" | "ollama");
     await config.save();
+
+    // Load models for the new provider and update the store
+    const models = await loadModels(providerId as "copilot" | "ollama");
+    appStore.setAvailableModels(models);
+
+    // If Ollama is selected and has models, open model selector
+    if (providerId === "ollama" && models.length > 0) {
+      appStore.setMode("model_select");
+    }
   };
 
 const createHandleCascadeToggle =
@@ -131,10 +147,13 @@ const createHandleSubmit =
 const execute = async (options: ChatTUIOptions): Promise<void> => {
   const ctx: ExecuteContext = {
     state: null,
+    baseSystemPrompt: null,
   };
 
   const { state, session } = await initializeChatService(options);
   ctx.state = state;
+  // Store the original system prompt before any agent modifications
+  ctx.baseSystemPrompt = state.systemPrompt;
 
   if (options.printMode && options.initialPrompt) {
     await executePrintMode(state, options.initialPrompt);