fix(coding-agent): backported pi-mono changes (1feccfed..b21b42d0)

packages/ai:
- feat: expose provider responseId on AssistantMessage
- feat: lazy-load provider modules for faster startup
- fix: hash foreign Responses API tool call IDs exceeding 64-char limit
- fix: ignore null chunks in openai-completions streams
- fix: keep image tool results inline for Gemini 3+ and Antigravity
- fix: correct Bedrock Claude 4.6 context window to 200k
- fix: support prompt caching for Bedrock application inference profiles
- fix: add OpenRouter reasoning payload format
- fix: ignore placeholder Vertex API keys
- fix: skip AJV validation in restricted runtimes
- fix: Anthropic OAuth client injection and responseId extraction
- fix: Codex incomplete/failed response status handling

packages/agent:
- fix: defer steering until after tool execution completes

packages/tui:
- feat: namespaced keybinding IDs with KeybindingsManager conflict detection
- feat: configurable select list column sizing (#2154 by @markusylisiurunen)
- fix: stream truncateToWidth for large strings
- fix: skip Termux height redraws
- fix: stop evicting unrelated default keybindings
- fix: resolve raw backspace ambiguity on Windows Terminal
- fix: clear stale scrollback on session switch (#2155 by @Perlence)
- fix: remove trailing markdown block spacing (#2152 by @markusylisiurunen)

packages/coding-agent:
- feat: add resizable share sidebar (#2435 by @dmmulroy)
- feat: emit OSC 133 command-executed marker
- feat: reload custom themes from disk watcher
- feat: add --fork session flag
- feat: file mutation queue for serialized writes
- feat: initial message consolidation utility
- fix: keybindings migrated to namespaced IDs
- fix: resolve waitForRetry() race when auto-retry produces tool calls
- fix: handle slash-delimited /model refs
- fix: refresh active model after provider updates
- fix: extended transient error patterns for retry

packages/tui/src/utils.ts

@@ -35,15 +35,25 @@ export function getSegmenter(): Intl.Segmenter {
 /**
  * Calculate the visible width of a string in terminal columns.
  */
+function _isPrintableAscii(str: string): boolean {
+	for (let i = 0; i < str.length; i++) {
+		const code = str.charCodeAt(i);
+		if (code < 0x20 || code > 0x7e) {
+			return false;
+		}
+	}
+	return true;
+}
+
 export function visibleWidthRaw(str: string): number {
 	if (!str) {
 		return 0;
 	}
 
 	// Fast path: pure ASCII printable
-	let isPureAscii = true;
 	let tabLength = 0;
 	const tabWidth = getDefaultTabWidth();
+	let isPureAscii = true;
 	for (let i = 0; i < str.length; i++) {
 		const code = str.charCodeAt(i);
 		if (code === 9) {