docs: document the BSDL workflow + add a batch/TUI tutorial

DESIGN.md: libbsdl dependency and --batch headless mode; bsdl_model/bsdl_check
in the layout; the attach-bsdl command and the `B` persist tag; PinSpec is now
BSDL-populated; verify's five passes incl. the model-driven and JTAG checks
and the new AnomalyKinds. README: libbsdl dependency, --batch usage, tutorial
link. New doc/user/tutorial.md: end-to-end batch and TUI walkthroughs (load →
tag → connect → attach-bsdl → verify, with the pin/JTAG findings explained).
Regenerated commands.md (adds attach-bsdl); index.md links the tutorial.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

doc/user/index.md

@@ -1,8 +1,9 @@
 # essim — user guide
 
-A short, task-oriented introduction to using essim. For an exhaustive
-reference of every command, see [`commands.md`](commands.md) (auto-
-generated from the binary). For scripting and `$variable` expansion,
+A short, task-oriented introduction to using essim. For step-by-step
+**batch** and **TUI** walkthroughs, see [`tutorial.md`](tutorial.md). For an
+exhaustive reference of every command, see [`commands.md`](commands.md)
+(auto-generated from the binary). For scripting and `$variable` expansion,
 see [`scripting.md`](scripting.md).
 
 ## What essim is
@@ -91,6 +92,8 @@ fresh.
 
 ## Where to look next
 
+- [`tutorial.md`](tutorial.md) — end-to-end batch and TUI walkthroughs,
+  including BSDL attach + the pin/JTAG checks.
 - [`commands.md`](commands.md) — exhaustive command reference,
   regenerated from the binary on every `cmake --build build --target doc`.
 - [`analysis.md`](analysis.md) — how essim classifies signals