feat(tui): add multiline paste mode in minimal UI

src/frontends/tui/commands.ts

@@ -2,6 +2,7 @@ export type Command =
   | { type: 'quit' }
   | { type: 'reset' }
   | { type: 'help' }
+  | { type: 'multiline' }
   | { type: 'status' }
   | { type: 'tools' }
   | { type: 'research'; task: string }
@@ -63,6 +64,11 @@ export function parseCommand(input: string): Command | null {
     return { type: 'help' };
   }
 
+  // Multiline paste mode
+  if (trimmed === '/paste' || trimmed === '/multiline') {
+    return { type: 'multiline' };
+  }
+
   // Status
   if (trimmed === '/status') {
     return { type: 'status' };
@@ -212,6 +218,7 @@ export function getHelpText(): string {
   return `
 Commands:
   /help, /?              Show this help
+  /paste, /multiline     Enter multiline mode (finish with single '.' line)
   /tools                 Show available tools in this session
   /model [name]          Show or switch model tier (local, default, fast, complex)
   /model <tier> <p/m>    Change tier's provider/model (e.g. /model default anthropic/claude-sonnet-4)
@@ -249,6 +256,8 @@ export type ModelAlias = 'local' | 'default' | 'fast' | 'complex' | 'opus' | 'so
 // List of all slash commands for autocompletion
 export const SLASH_COMMANDS = [
   '/help',
+  '/paste',
+  '/multiline',
   '/tools',
   '/model',
   '/backend',
@@ -279,6 +288,8 @@ export const SLASH_COMMANDS = [
 // Command descriptions for tooltips
 export const COMMAND_TOOLTIPS: Record<string, string> = {
   '/help': 'Show available commands',
+  '/paste': 'Compose a multiline message; finish with a single "." line',
+  '/multiline': 'Compose a multiline message; finish with a single "." line',
   '/tools': 'Show authoritative runtime tool list for this session',
   '/model': 'Show or switch model (local, default, fast, complex)',
   '/backend': 'Show or switch local backend (ollama, llamacpp)',