refactor: extract range_to_rfc3339 into shared scripts/lib-time

Removes duplicated ~35-line function from axiom-metrics-query and
axiom-metrics-discover. Both now source scripts/lib-time instead.

Addresses Cursor Bugbot review feedback on PR #6.

Thread: https://ampcode.com/threads/T-019c50fb-ca56-7198-b6aa-7e14a4b01273
Co-authored-by: Amp <amp@ampcode.com>
Amp-Thread-ID: https://ampcode.com/threads/T-019c50fb-ca56-7198-b6aa-7e14a4b01273

Author: Licenser

scripts/axiom-metrics-discover

@@ -74,43 +74,8 @@ shift
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 
-# Compute RFC3339 start/end from --range if provided
-# range_to_rfc3339 converts a human range (e.g. 1h, 24h, 7d) to an RFC3339 timestamp that many seconds ago
-range_to_rfc3339() {
-  local range="$1"
-  local value="${range%[hdm]}"
-  local suffix="${range: -1}"
-
-  if ! [[ "$value" =~ ^[0-9]+$ ]]; then
-    echo "Error: Invalid range value '$range'. Expected number + suffix (h/d/m)." >&2
-    return 1
-  fi
-
-  case "$suffix" in
-    h) local label="hour" ;;
-    d) local label="day" ;;
-    m) local label="minute" ;;
-    *)
-      echo "Error: Invalid range suffix '$suffix'. Use h (hours), d (days), or m (minutes)." >&2
-      return 1
-      ;;
-  esac
-
-  # Try GNU date first (linux, or gdate on macOS), then fall back to macOS date
-  if date -u -d "1 hour ago" +%Y-%m-%dT%H:%M:%SZ &>/dev/null; then
-    # GNU date
-    date -u -d "$value $label ago" +%Y-%m-%dT%H:%M:%SZ
-  else
-    # macOS date: -v flag with uppercase suffix
-    local date_flag
-    case "$suffix" in
-      h) date_flag="-v-${value}H" ;;
-      d) date_flag="-v-${value}d" ;;
-      m) date_flag="-v-${value}M" ;;
-    esac
-    date -u "$date_flag" +%Y-%m-%dT%H:%M:%SZ
-  fi
-}
+# shellcheck disable=SC1091
+source "$SCRIPT_DIR/lib-time"
 
 # Validate time arguments
 if [[ -n "$RANGE" && ( -n "$START_TIME" || -n "$END_TIME" ) ]]; then

scripts/axiom-metrics-query

@@ -104,43 +104,8 @@ if [[ -t 0 ]]; then
   exit 1
 fi
 
-# Compute RFC3339 start/end from --range if provided
-# range_to_rfc3339 converts a human range (e.g. 1h, 24h, 7d) to an RFC3339 timestamp that many seconds ago
-range_to_rfc3339() {
-  local range="$1"
-  local value="${range%[hdm]}"
-  local suffix="${range: -1}"
-
-  if ! [[ "$value" =~ ^[0-9]+$ ]]; then
-    echo "Error: Invalid range value '$range'. Expected number + suffix (h/d/m)." >&2
-    return 1
-  fi
-
-  case "$suffix" in
-    h) local label="hour" ;;
-    d) local label="day" ;;
-    m) local label="minute" ;;
-    *)
-      echo "Error: Invalid range suffix '$suffix'. Use h (hours), d (days), or m (minutes)." >&2
-      return 1
-      ;;
-  esac
-
-  # Try GNU date first (linux, or gdate on macOS), then fall back to macOS date
-  if date -u -d "1 hour ago" +%Y-%m-%dT%H:%M:%SZ &>/dev/null; then
-    # GNU date
-    date -u -d "$value $label ago" +%Y-%m-%dT%H:%M:%SZ
-  else
-    # macOS date: -v flag with uppercase suffix
-    local date_flag
-    case "$suffix" in
-      h) date_flag="-v-${value}H" ;;
-      d) date_flag="-v-${value}d" ;;
-      m) date_flag="-v-${value}M" ;;
-    esac
-    date -u "$date_flag" +%Y-%m-%dT%H:%M:%SZ
-  fi
-}
+# shellcheck disable=SC1091
+source "$SCRIPT_DIR/lib-time"
 
 # Validate time arguments
 if [[ -n "$RANGE" && ( -n "$START_TIME" || -n "$END_TIME" ) ]]; then

scripts/lib-time

@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+# Shared time utilities for Gilfoyle scripts
+# Source this file: source "$SCRIPT_DIR/lib-time"
+
+# range_to_rfc3339 converts a human range (e.g. 1h, 24h, 7d) to an RFC3339 timestamp that many seconds ago
+range_to_rfc3339() {
+  local range="$1"
+  local value="${range%[hdm]}"
+  local suffix="${range: -1}"
+
+  if ! [[ "$value" =~ ^[0-9]+$ ]]; then
+    echo "Error: Invalid range value '$range'. Expected number + suffix (h/d/m)." >&2
+    return 1
+  fi
+
+  case "$suffix" in
+    h) local label="hour" ;;
+    d) local label="day" ;;
+    m) local label="minute" ;;
+    *)
+      echo "Error: Invalid range suffix '$suffix'. Use h (hours), d (days), or m (minutes)." >&2
+      return 1
+      ;;
+  esac
+
+  # Try GNU date first (linux, or gdate on macOS), then fall back to macOS date
+  if date -u -d "1 hour ago" +%Y-%m-%dT%H:%M:%SZ &>/dev/null; then
+    # GNU date
+    date -u -d "$value $label ago" +%Y-%m-%dT%H:%M:%SZ
+  else
+    # macOS date: -v flag with uppercase suffix
+    local date_flag
+    case "$suffix" in
+      h) date_flag="-v-${value}H" ;;
+      d) date_flag="-v-${value}d" ;;
+      m) date_flag="-v-${value}M" ;;
+    esac
+    date -u "$date_flag" +%Y-%m-%dT%H:%M:%SZ
+  fi
+}