refactor(shared): deduplicate shared/ utilities against coding-agent package exports

- Add packages/coding-agent/src/utils/format.ts as the canonical source
  for formatDuration, formatTokenCount, truncateWithEllipsis, sparkline,
  formatDateShort, fileLink, stripAnsi, normalizeStringArray — all already
  exported from @singularity-forge/coding-agent via index.ts.

- Convert shared/format-utils.js to a compatibility shim that re-exports
  the 8 functions from @singularity-forge/coding-agent. All 13 importers
  continue to work with no import changes required.

- Convert shared/path-display.js to a compatibility shim that re-exports
  toPosixPath from @singularity-forge/coding-agent. Implementation in
  packages/coding-agent/src/utils/path-display.ts was already canonical.

- shared/frontmatter.js is intentionally NOT shimmed: splitFrontmatter/
  parseFrontmatterMap have a different API from the package's parseFrontmatter/
  stripFrontmatter (flat-map vs {frontmatter, body} object).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

packages/coding-agent/src/utils/format.ts

@@ -0,0 +1,118 @@
+/**
+ * Pure formatting utilities shared across extensions and the core agent.
+ *
+ * Purpose: centralise widely-used, dependency-free format helpers so extension
+ * shared/ shims can re-export from the package rather than duplicating source.
+ * No @singularity-forge/tui dependency — safe for any import context.
+ *
+ * Consumer: 35+ bundled extensions via src/resources/extensions/shared/format-utils.js.
+ */
+
+// ─── Duration Formatting ──────────────────────────────────────────────────────
+
+/** Format a millisecond duration as a compact human-readable string. */
+export function formatDuration(ms: number): string {
+	if (ms > 0 && ms < 1000) return `${ms}ms`;
+	const s = Math.floor(ms / 1000);
+	if (s < 60) return `${s}s`;
+	const m = Math.floor(s / 60);
+	const rs = s % 60;
+	if (m < 60) return `${m}m ${rs}s`;
+	const h = Math.floor(m / 60);
+	const rm = m % 60;
+	return `${h}h ${rm}m`;
+}
+
+// ─── Token Count Formatting ──────────────────────────────────────────────────
+
+/** Format a token count as a compact human-readable string (e.g. 1.5k, 1.50M). */
+export function formatTokenCount(count: number): string {
+	if (count < 1000) return `${count}`;
+	if (count < 1_000_000) return `${(count / 1000).toFixed(1)}k`;
+	return `${(count / 1_000_000).toFixed(2)}M`;
+}
+
+// ─── Text Truncation ─────────────────────────────────────────────────────────
+
+/** Truncate a string to `maxLength` characters, replacing the last character with an ellipsis if needed. */
+export function truncateWithEllipsis(text: string, maxLength: number): string {
+	if (text.length <= maxLength) return text;
+	return text.slice(0, maxLength - 1) + "…";
+}
+
+// ─── Data Visualization ───────────────────────────────────────────────────────
+
+/**
+ * Render a sparkline from numeric values using Unicode block characters.
+ * Uses loop-based max to avoid stack overflow on large arrays.
+ */
+export function sparkline(values: number[]): string {
+	if (values.length === 0) return "";
+	const chars = "▁▂▃▄▅▆▇█";
+	let max = 0;
+	for (const v of values) {
+		if (v > max) max = v;
+	}
+	if (max === 0) return chars[0].repeat(values.length);
+	return values
+		.map((v) => chars[Math.min(7, Math.floor((v / max) * 7))])
+		.join("");
+}
+
+// ─── Date Formatting ─────────────────────────────────────────────────────────
+
+/** Format an ISO date string as a compact locale string (e.g. "Mar 17, 2025, 02:30 PM"). */
+export function formatDateShort(iso: string): string {
+	try {
+		const d = new Date(iso);
+		return d.toLocaleString("en-US", {
+			month: "short",
+			day: "numeric",
+			year: "numeric",
+			hour: "2-digit",
+			minute: "2-digit",
+		});
+	} catch {
+		return iso;
+	}
+}
+
+// ─── Hyperlinks ──────────────────────────────────────────────────────────────
+
+/** Wrap text in an OSC 8 hyperlink for terminals that support clickable links. */
+export function fileLink(filePath: string, displayText?: string): string {
+	const uri = `file://${filePath}`;
+	const label = displayText ?? filePath;
+	return `\x1b]8;;${uri}\x07${label}\x1b]8;;\x07`;
+}
+
+// ─── ANSI Stripping ───────────────────────────────────────────────────────────
+
+/** Strip ANSI escape sequences from a string. */
+export function stripAnsi(s: string): string {
+	return s.replace(/\x1b\[[0-9;]*m/g, "");
+}
+
+// ─── String Array Normalization ─────────────────────────────────────────────
+
+export interface NormalizeStringArrayOptions {
+	/** Deduplicate items after filtering and trimming. */
+	dedupe?: boolean;
+}
+
+/**
+ * Normalize an unknown value to a string array.
+ * Filters to string items, trims whitespace, removes empty strings.
+ * Optionally deduplicates.
+ */
+export function normalizeStringArray(
+	value: unknown,
+	options?: NormalizeStringArrayOptions,
+): string[] {
+	if (!Array.isArray(value)) return [];
+	const items = (value as unknown[])
+		.filter((item): item is string => typeof item === "string")
+		.map((item) => item.trim())
+		.filter(Boolean);
+	return options?.dedupe ? [...new Set(items)] : items;
+}

src/resources/extensions/shared/format-utils.js

@@ -1,93 +1,20 @@
 /**
- * Shared pure formatting utilities — no @singularity-forge/tui dependency.
+ * Compatibility shim — re-exports pure formatting utilities from the
+ * canonical implementation in @singularity-forge/coding-agent.
+ *
+ * All 13 importers of this module continue to work without any import changes.
+ * The implementations now live in packages/coding-agent/src/utils/format.ts.
  *
  * ANSI-aware layout helpers (padRight, joinColumns, centerLine, fitColumns)
- * live in layout-utils.ts to avoid pulling @singularity-forge/tui into modules that
+ * still live in layout-utils.js (depend on @singularity-forge/tui).
- * run outside jiti's alias resolution (e.g. HTML report generation via
- * dynamic import in auto-loop).
  */
-// ─── Duration Formatting ──────────────────────────────────────────────────────
+export {
-/** Format a millisecond duration as a compact human-readable string. */
+	fileLink,
-export function formatDuration(ms) {
+	formatDateShort,
-	if (ms > 0 && ms < 1000) return `${ms}ms`;
+	formatDuration,
-	const s = Math.floor(ms / 1000);
+	formatTokenCount,
-	if (s < 60) return `${s}s`;
+	normalizeStringArray,
-	const m = Math.floor(s / 60);
+	sparkline,
-	const rs = s % 60;
+	stripAnsi,
-	if (m < 60) return `${m}m ${rs}s`;
+	truncateWithEllipsis,
-	const h = Math.floor(m / 60);
+} from "@singularity-forge/coding-agent";
-	const rm = m % 60;
-	return `${h}h ${rm}m`;
-}
-// ─── Token Count Formatting ──────────────────────────────────────────────────
-/** Format a token count as a compact human-readable string (e.g. 1.5k, 1.50M). */
-export function formatTokenCount(count) {
-	if (count < 1000) return `${count}`;
-	if (count < 1_000_000) return `${(count / 1000).toFixed(1)}k`;
-	return `${(count / 1_000_000).toFixed(2)}M`;
-}
-// ─── Text Truncation ─────────────────────────────────────────────────────────
-/** Truncate a string to `maxLength` characters, replacing the last character with an ellipsis if needed. */
-export function truncateWithEllipsis(text, maxLength) {
-	if (text.length <= maxLength) return text;
-	return text.slice(0, maxLength - 1) + "…";
-}
-// ─── Data Visualization ───────────────────────────────────────────────────────
-/**
- * Render a sparkline from numeric values using Unicode block characters.
- * Uses loop-based max to avoid stack overflow on large arrays.
- */
-export function sparkline(values) {
-	if (values.length === 0) return "";
-	const chars = "\u2581\u2582\u2583\u2584\u2585\u2586\u2587\u2588";
-	let max = 0;
-	for (const v of values) {
-		if (v > max) max = v;
-	}
-	if (max === 0) return chars[0].repeat(values.length);
-	return values
-		.map((v) => chars[Math.min(7, Math.floor((v / max) * 7))])
-		.join("");
-}
-// ─── Date Formatting ─────────────────────────────────────────────────────────
-/** Format an ISO date string as a compact locale string (e.g. "Mar 17, 2025, 02:30 PM"). */
-export function formatDateShort(iso) {
-	try {
-		const d = new Date(iso);
-		return d.toLocaleString("en-US", {
-			month: "short",
-			day: "numeric",
-			year: "numeric",
-			hour: "2-digit",
-			minute: "2-digit",
-		});
-	} catch {
-		return iso;
-	}
-}
-// ─── Hyperlinks ──────────────────────────────────────────────────────────────
-/** Wrap text in an OSC 8 hyperlink for terminals that support clickable links. */
-export function fileLink(filePath, displayText) {
-	const uri = `file://${filePath}`;
-	const label = displayText ?? filePath;
-	return `\x1b]8;;${uri}\x07${label}\x1b]8;;\x07`;
-}
-// ─── ANSI Stripping ───────────────────────────────────────────────────────────
-/** Strip ANSI escape sequences from a string. */
-export function stripAnsi(s) {
-	return s.replace(/\x1b\[[0-9;]*m/g, "");
-}
-// ─── String Array Normalization ─────────────────────────────────────────────
-/**
- * Normalize an unknown value to a string array.
- * Filters to string items, trims whitespace, removes empty strings.
- * Optionally deduplicates.
- */
-export function normalizeStringArray(value, options) {
-	if (!Array.isArray(value)) return [];
-	const items = value
-		.filter((item) => typeof item === "string")
-		.map((item) => item.trim())
-		.filter(Boolean);
-	return options?.dedupe ? [...new Set(items)] : items;
-}

src/resources/extensions/shared/path-display.js

@@ -1,18 +1,12 @@
 /**
- * Cross-platform path display for LLM-visible text.
+ * Compatibility shim — re-exports toPosixPath from the canonical
+ * implementation in @singularity-forge/coding-agent.
  *
- * Paths injected into prompts, tool results, or extension messages must use
+ * All importers of this module continue to work without any import changes.
- * forward slashes. Windows backslash paths cause bash failures when the model
+ * The implementation now lives in packages/coding-agent/src/utils/path-display.ts.
- * copies them into shell commands — bash interprets backslashes as escape chars.
  *
- * Use this ONLY for paths entering text the LLM or shell sees.
+ * Use ONLY for paths entering text the LLM or shell sees.
  * Filesystem operations (fs.readFile, path.join, spawn cwd) handle native
  * separators correctly and should NOT be normalized.
  */
-/**
+export { toPosixPath } from "@singularity-forge/coding-agent";
- * Convert a filesystem path to forward-slash form for display in LLM text.
- * No-op on Unix. On Windows converts `C:\Users\name` to `C:/Users/name`.
- */
-export function toPosixPath(fsPath) {
-	return fsPath.replaceAll("\\", "/");
-}