refactor(cli): Replace tracing-indicatif with shared MultiProgress

tracing-indicatif pulled in vt100, arrayvec, and its own indicatif
integration layer. Replace it with a minimal SuspendingWriter that
coordinates tracing output with progress bars via a global LazyLock
MultiProgress.

- Add src/cli/progress.rs: shared MultiProgress singleton via LazyLock
  and a SuspendingWriter that suspends bars before writing log lines,
  preventing interleaving/flicker
- Wire all progress bar creation through multi().add() in sync and
  ingest commands
- Replace IndicatifLayer in main.rs with SuspendingWriter for
  tracing-subscriber's fmt layer
- Remove tracing-indicatif from Cargo.toml (drops vt100 and arrayvec
  transitive deps)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/cli/commands/sync.rs

@@ -40,7 +40,7 @@ fn stage_spinner(stage: u8, total: u8, msg: &str, robot_mode: bool) -> ProgressB
     if robot_mode {
         return ProgressBar::hidden();
     }
-    let pb = ProgressBar::new_spinner();
+    let pb = crate::cli::progress::multi().add(ProgressBar::new_spinner());
     pb.set_style(
         ProgressStyle::default_spinner()
             .template("{spinner:.blue} {msg}")