feat(android): Tauri 2.x mobile build infrastructure

Adds infrastructure for building the Tauri 2.x Android app (the pivot
away from the Kotlin+JNI approach whose stack overflow / libcrypto TLS
crash / thread lifecycle hell is documented in the incident report):

- scripts/Dockerfile.android-builder: extended to support both the
  legacy Kotlin+JNI pipeline (cargo-ndk + Gradle) and the new Tauri
  mobile pipeline (tauri-cli + Node/npm). Adds Node.js 20 LTS, API
  level 36 + build-tools 35.0.0, and additional apt packages.
- scripts/build-tauri-android.sh: fire-and-forget remote build via
  Docker on SepehrHomeserverdk, with ntfy.sh notifications and
  rustypaste upload of the resulting APK. Mirrors the pattern of
  build-tauri-android-docker.sh but targets the new Tauri pipeline.
- docs/incident-tauri-android-init-tcb.md: postmortem of the Kotlin+JNI
  crash cascade that drove the Tauri mobile rewrite decision. Covers
  the __init_tcb / pthread_create bionic private symbol leak, the
  staticlib + cdylib crate-type interaction, the Dispatchers.IO 512 KB
  thread stack overflow, and the tokio runtime / libcrypto TLS race.
- scripts/mint-tmux.sh, scripts/prep-linux-mint.sh: general dev
  infrastructure (tmux + Linux Mint workstation prep scripts).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/mint-tmux.sh

@@ -0,0 +1,72 @@
+#!/usr/bin/env bash
+# =============================================================================
+# mint-tmux.sh — run a command inside a persistent tmux session on the
+# Linux Mint build box so the user can attach and watch/interact at any time.
+#
+# Usage:
+#   mint-tmux.sh run   <window-name> <command...>   # start a new tmux window
+#   mint-tmux.sh send  <window-name> <text...>      # send keys to a window
+#   mint-tmux.sh kill  <window-name>                # close a window
+#   mint-tmux.sh list                               # list windows
+#   mint-tmux.sh tail  <window-name>                # dump last 200 lines
+#
+# Session name is always "wzp". Attach manually with:
+#   ssh -t root@172.16.81.192 tmux attach -t wzp
+#
+# If the wzp session doesn't exist yet, it's created automatically.
+# =============================================================================
+set -euo pipefail
+
+HOST="root@172.16.81.192"
+SESSION="wzp"
+SSH_OPTS="-o ConnectTimeout=10 -o LogLevel=ERROR"
+
+ensure_session() {
+    ssh $SSH_OPTS "$HOST" "
+        tmux has-session -t $SESSION 2>/dev/null || tmux new-session -d -s $SESSION -n home 'bash -l'
+    "
+}
+
+cmd="${1:-list}"
+shift || true
+
+case "$cmd" in
+    run)
+        WIN="${1:?window name required}"; shift
+        ensure_session
+        # Use a heredoc so multi-arg commands don't need escaping
+        CMD="$*"
+        ssh $SSH_OPTS "$HOST" bash -s <<REMOTE
+            if tmux list-windows -t $SESSION -F '#W' 2>/dev/null | grep -qx '$WIN'; then
+                tmux kill-window -t $SESSION:$WIN 2>/dev/null || true
+            fi
+            tmux new-window -t $SESSION -n '$WIN' "bash -l -c '$CMD; echo; echo --- window $WIN exited with code \\\$?; exec bash -l'"
+REMOTE
+        echo "Started '$WIN' in tmux session $SESSION on $HOST"
+        echo "Attach: ssh -t $HOST tmux attach -t $SESSION"
+        ;;
+    send)
+        WIN="${1:?window name required}"; shift
+        TEXT="$*"
+        ssh $SSH_OPTS "$HOST" "tmux send-keys -t $SESSION:$WIN '$TEXT' C-m"
+        ;;
+    kill)
+        WIN="${1:?window name required}"
+        ssh $SSH_OPTS "$HOST" "tmux kill-window -t $SESSION:$WIN 2>/dev/null || true"
+        ;;
+    list)
+        ensure_session
+        ssh $SSH_OPTS "$HOST" "tmux list-windows -t $SESSION"
+        ;;
+    tail)
+        WIN="${1:?window name required}"
+        ssh $SSH_OPTS "$HOST" "tmux capture-pane -p -t $SESSION:$WIN -S -200 || echo 'no such window'"
+        ;;
+    attach)
+        exec ssh -t $SSH_OPTS "$HOST" tmux attach -t $SESSION
+        ;;
+    *)
+        sed -n '3,20p' "$0"
+        exit 1
+        ;;
+esac