v1.5.0: invalid-INS one-byte re-frame + explicit discard logging

Residual CONCAT mis-frames (4gmodem/A55_sim2/S21p_sim2) traced to a silent
5-byte drop at an invalid-INS T=0 header (0x0f 00 a4 08 04). Drop only the
stray leading byte and re-frame the remaining four via _replay so the real
command (00 a4 08 04 02 2f 00 -> 61 1c) is recovered.

- _note_discard()/_consume_first(): every consumed-but-unemitted byte is
  now logged; idle 0x00/0xFF discards are rate-limited, real data always
  gets an ANN_WARN annotation.
- All read-until-SW loops log skipped non-SW bytes.
- All traces: CONCAT 0; BAD_FCS/GARBAGE 0; test_8/test_7 RESULT OK;
  47/47 unit tests; baseline byte-identical.

History rewritten to a single root commit so no example trace is stored
in the repo (fixtures are local-only, gitignored). README keeps only
generic <trace>.sr placeholders; AGENTS.md retains the fixture names.

setup.sh

@@ -0,0 +1,97 @@
+#!/bin/bash
+# sigrok_iso7816_stream setup: verify sigrok-cli and register the decoder.
+set -euo pipefail
+
+REPO_DIR="$(cd "$(dirname "$0")" && pwd)"
+DECODERS_DIR="${HOME}/.local/share/libsigrokdecode/decoders"
+LINK="${DECODERS_DIR}/iso7816"
+FIRMWARE_DIRS=(
+    /usr/share/sigrok-firmware
+    /usr/share/sigrok/firmware
+    /usr/local/share/sigrok-firmware
+)
+
+printf 'Checking sigrok-cli... '
+if ! command -v sigrok-cli >/dev/null 2>&1; then
+    echo "NOT FOUND"
+    echo "  Install it first, e.g.: sudo apt install sigrok-cli"
+    exit 1
+fi
+echo "found ($(command -v sigrok-cli))"
+sigrok-cli --version 2>/dev/null | sed 's/^/  /'
+
+printf 'Checking FX2 firmware... '
+FW_FOUND=""
+for dir in "${FIRMWARE_DIRS[@]}"; do
+    if compgen -G "${dir}/fx2lafw-*.fw" >/dev/null; then
+        FW_FOUND="${dir}"
+        break
+    fi
+done
+if [ -z "${FW_FOUND}" ]; then
+    echo "NOT FOUND"
+    echo "  fx2lafw firmware files are missing."
+    echo "  Arch/CachyOS: sudo pacman -S sigrok-firmware-fx2lafw"
+    echo "  Debian/Ubuntu: sudo apt install sigrok-firmware-fx2lafw"
+    exit 1
+fi
+echo "ok (${FW_FOUND})"
+
+printf 'Checking decoder directory... '
+mkdir -p "${DECODERS_DIR}"
+echo "ok (${DECODERS_DIR})"
+
+printf 'Installing decoder symlink... '
+if [ -L "${LINK}" ]; then
+    rm "${LINK}"
+elif [ -e "${LINK}" ]; then
+    echo ""
+    echo "  ${LINK} exists and is not a symlink; refusing to overwrite." >&2
+    exit 1
+fi
+ln -s "${REPO_DIR}" "${LINK}"
+echo "ok"
+
+printf 'Verifying... '
+target="$(readlink -f "${LINK}")"
+if [ "${target}" = "${REPO_DIR}" ] && [ -f "${target}/pd.py" ]; then
+    echo "ok (${LINK} -> ${target})"
+else
+    echo "FAILED" >&2
+    exit 1
+fi
+
+printf 'Probing hardware max samplerate... '
+MAX_RATE=""
+DEVICE_MSG=""
+for rate in 1M 2M 4M 8M 12M 16M 20M 24M; do
+    result="$(sigrok-cli -d fx2lafw --config "samplerate=${rate}" --continuous \
+        --time 20 -P 'iso7816:clk=D0:data=D1' 2>&1 || true)"
+    if echo "${result}" | grep -q "Unable to claim"; then
+        DEVICE_MSG="blocked (another program holds the device; stop it and re-run)"
+        break
+    fi
+    if echo "${result}" | grep -q "Failed to open device\|No devices found"; then
+        DEVICE_MSG="skipped (no FX2 device connected)"
+        break
+    fi
+    if ! echo "${result}" | grep -qE "invalid argument|Unable to sample|Could not start"; then
+        MAX_RATE="${rate}"
+    fi
+done
+
+if [ -n "${DEVICE_MSG}" ]; then
+    echo "${DEVICE_MSG}"
+elif [ -n "${MAX_RATE}" ]; then
+    echo "${MAX_RATE}"
+    if [ "${MAX_RATE}" != "24M" ]; then
+        echo "  Device rejects rates above ${MAX_RATE}. Rates up to 24 MHz need"
+        echo "  8-bit sampling: only channels D0-D7 may be enabled (enabling"
+        echo "  A0/analog forces 16-bit collection, capped at 12 MHz)."
+        echo "  start.sh restricts channels accordingly."
+    fi
+else
+    echo "unknown (device present but no rate accepted)"
+fi
+
+echo "Done. Run ./start.sh to begin capture."