fix(examples): use arlog_rel! for help banner and prompt UI per review

Converts the 16 help-banner eprintln! sites in generate_patt.rs and the
5 surrounding eprintln! calls in nft_marker_gen.rs y/N prompt block to
arlog_rel!, which routes through the arlog system without applying a
severity prefix. This was the correct macro for help text and prompt UI;
my original PR kept these as eprintln! because I missed arlog_rel! in the
arlog macro family.

eprint!("Continue anyway? [y/N] ") at nft_marker_gen.rs:152 left as-is
per maintainer guidance -- interactive prompts need synchronous stderr
behavior that a log facade may not guarantee.

Empty blank-line spacers (formerly empty eprintln!()) use arlog_rel!("")
because bare arlog_rel!() does not compile -- the macro accepts
$($arg:tt)* but forwards to log::log! which requires $($arg:tt)+.
Observable output is identical (the arlog::rel formatter is prefix-free,
so an empty message renders as a bare newline).

Verified generate_patt --help output is plain text with zero
[info]/[warning]/[error] prefixes.

Addresses review comments on PR 3 / #90.

Author: maxwelljhuang

crates/core/examples/generate_patt.rs

@@ -10,7 +10,7 @@ use std::path::Path;
 use std::str::FromStr;
 use webarkitlib_rs::pattern::{ar_patt_get_image2, ar_patt_save};
 use webarkitlib_rs::types::{ARMarkerInfo, ARParam, ARParamLT, ARParamLTf, ARPixelFormat};
-use webarkitlib_rs::{arlog_e, arlog_i, arlog_w};
+use webarkitlib_rs::{arlog_e, arlog_i, arlog_rel, arlog_w};
 
 /*
  English documentation / notes for this example
@@ -75,24 +75,24 @@ use webarkitlib_rs::{arlog_e, arlog_i, arlog_w};
 */
 
 fn print_help_and_exit() {
-    eprintln!("generate_patt example — usage:");
-    eprintln!("  --input PATH           input image (default: examples/Data/HIRO-test.jpg)");
-    eprintln!("  --out PATH             output .patt path (default: ./crates/core/examples/Data/generated.patt)");
-    eprintln!("  --camera PATH          camera_para.dat path to build ARParamLT (optional)");
-    eprintln!("  --border N             add black border of N pixels around input (default: 0)");
-    eprintln!("  --patt-size N          pattern size in pixels (default: 16)");
-    eprintln!(
+    arlog_rel!("generate_patt example — usage:");
+    arlog_rel!("  --input PATH           input image (default: examples/Data/HIRO-test.jpg)");
+    arlog_rel!("  --out PATH             output .patt path (default: ./crates/core/examples/Data/generated.patt)");
+    arlog_rel!("  --camera PATH          camera_para.dat path to build ARParamLT (optional)");
+    arlog_rel!("  --border N             add black border of N pixels around input (default: 0)");
+    arlog_rel!("  --patt-size N          pattern size in pixels (default: 16)");
+    arlog_rel!(
         "  --sample-factor N      sample factor multiplier passed to extraction (default: 4)"
     );
-    eprintln!("  --flip-v               flip input image vertically before processing");
-    eprintln!("  --channel-order rgb|bgr interpret input buffer as rgb or bgr (default: rgb)");
-    eprintln!("  --with-border          indicate the INPUT IMAGE ALREADY CONTAINS THE MARKER BORDER (no auto-add)");
-    eprintln!("  --patt-ratio F         pattern ratio (pattern/(pattern+2*border)), default 0.5");
-    eprintln!("  --batch                run automatic experiments and write CSV report");
-    eprintln!("  --quiet                reduce printed output");
-    eprintln!("  --verbose              print verbose diagnostic info (full_side, min_dim) when border is auto-computed");
-    eprintln!("  --debug                print very verbose intermediate extraction values (threshold, bbox, vertices, params)");
-    eprintln!("  --help                 show this help");
+    arlog_rel!("  --flip-v               flip input image vertically before processing");
+    arlog_rel!("  --channel-order rgb|bgr interpret input buffer as rgb or bgr (default: rgb)");
+    arlog_rel!("  --with-border          indicate the INPUT IMAGE ALREADY CONTAINS THE MARKER BORDER (no auto-add)");
+    arlog_rel!("  --patt-ratio F         pattern ratio (pattern/(pattern+2*border)), default 0.5");
+    arlog_rel!("  --batch                run automatic experiments and write CSV report");
+    arlog_rel!("  --quiet                reduce printed output");
+    arlog_rel!("  --verbose              print verbose diagnostic info (full_side, min_dim) when border is auto-computed");
+    arlog_rel!("  --debug                print very verbose intermediate extraction values (threshold, bbox, vertices, params)");
+    arlog_rel!("  --help                 show this help");
     std::process::exit(0);
 }
 

crates/core/examples/nft_marker_gen.rs

@@ -64,6 +64,8 @@ use clap::Parser;
 use std::path::Path;
 use std::time::Instant;
 use webarkitlib_rs::ar2::{ar2_gen_feature_map, ar2_gen_image_set};
+#[cfg(not(feature = "ffi-backend"))]
+use webarkitlib_rs::arlog_rel;
 #[cfg(feature = "ffi-backend")]
 use webarkitlib_rs::arlog_w;
 use webarkitlib_rs::{arlog_e, arlog_i};
@@ -142,22 +144,22 @@ fn main() {
     {
         use std::io::Write as _;
         if !cli.yes {
-            eprintln!();
-            eprintln!(
+            arlog_rel!("");
+            arlog_rel!(
                 "Warning: built without `ffi-backend` feature — .fset3 will NOT be generated."
             );
-            eprintln!("An NFT marker without .fset3 cannot be used for initialization/detection.");
+            arlog_rel!("An NFT marker without .fset3 cannot be used for initialization/detection.");
             eprint!("Continue anyway? [y/N] ");
             let _ = std::io::stdout().flush();
             let mut answer = String::new();
             std::io::stdin()
                 .read_line(&mut answer)
                 .expect("failed to read input");
             if !answer.trim().eq_ignore_ascii_case("y") {
-                eprintln!("Aborted.");
+                arlog_rel!("Aborted.");
                 std::process::exit(1);
             }
-            eprintln!();
+            arlog_rel!("");
         }
     }