Add multiplayer bots, typing languages, and rework the UI layout

Multiplayer
- Quick match: POST /api/multiplayer/quickmatch returns whichever room is
  still filling, or opens one. Players never see a room code; joining by
  code stays for racing specific people.
- Bots fill quick-match rooms after a short wait so a new game is never an
  empty lobby. They only ever join quick-match rooms, never a room opened
  by code. One or two per room, drawn from separate ~40 and ~80 WPM tiers so
  two bots are never near each other's pace, and they stall to correct
  mistakes rather than typing a clean straight line.
- Live player count via GET /api/multiplayer/online, shown on the
  Multiplayer control and under the main menu's Multiplayer button.
- Per-racer colours: you are the theme accent, opponents take distinct hues
  that stay the same from lobby to race.
- The countdown no longer holds the room lock for its full three seconds,
  which is what reset clients mid-countdown.

Typing languages
- 16 languages for the generated-word modes, each with its own
  high-frequency vocabulary rather than a translation of the English list.
- Picker in the top-right rail; non-English uses its own list at every
  difficulty tier instead of falling back to English words.

Fix UTF-8 accuracy in the game core
- update_game_state mixed byte and character counts: total_characters_typed
  accumulated byte-length deltas while total_correct_characters compared a
  char index against that byte count. Equal on ASCII, so it went unnoticed;
  a correctly typed Spanish passage scored 6%. The old byte slicing would
  also have panicked if an index landed inside a multi-byte character.
  Rewritten char-based, with regression tests.

Programming mode
- Replaced prose about programming with real code: 26 syntax-highlighted
  snippets across JavaScript, Python, Rust, C/Go/Java and shell. Single-line
  by necessity, since the typing input is a single-line field.

Layout and readability
- One icon rail arrangement on every screen: Settings/Store under the
  wordmark, Language/Theme/Friends/Account top-right, Stats/Leaderboard/
  Multiplayer bottom-right.
- Main menu: mode picker moved out of the Single Player button, which it was
  notching a divider through and pushing the label off-centre.
- Escape returns to the menu, closing any open popover first, and confirms
  before abandoning a live race.
- Split --text-color and --sub-color per theme; they shared one value that
  measured 3.65:1 against the background, below the 4.5:1 body-text floor.
- Semantic colours used in exactly one place each: gold for a personal best,
  amber for the race countdown and the mobile-result badge.
- Passage now sits in the same place on the typing and end screens, and its
  column is a whole number of characters wide so wrapping cannot leave a
  permanent gap on the right.
- End screen: keystrokes and a correct/wrong/extra/missed split, attribution
  carried over from the typing screen, and a graph with a separate error
  axis, axis titles including seconds, and smoothed lines.

1 files changed, 78 insertions, 0 deletions

diff --git a/web/launch.sh b/web/launch.sh
new file mode 100755
index 0000000..bcde2d6
--- /dev/null
+++ b/web/launch.sh
@@ -0,0 +1,78 @@
+#!/bin/bash
+
+# Colors for output
+GREEN='\033[0;32m'
+BLUE='\033[0;34m'
+RED='\033[0;31m'
+NC='\033[0m' # No Color
+YELLOW='\033[0;33m'
+
+echo -e "${BLUE}Starting TyperPunk Web...${NC}"
+
+# Resolve directories
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+ROOT_DIR="${SCRIPT_DIR}/.."
+
+# Ensure wasm-pack is available (auto-install if possible)
+if ! command -v wasm-pack &> /dev/null; then
+  echo -e "${YELLOW}wasm-pack not found. Attempting to install via cargo...${NC}"
+  if command -v cargo &> /dev/null; then
+    cargo install wasm-pack || {
+      echo -e "${RED}Failed to install wasm-pack automatically. Please install manually: cargo install wasm-pack${NC}"
+      exit 1
+    }
+  else
+    echo -e "${RED}Rust cargo is not installed. Please install Rust and then run: cargo install wasm-pack${NC}"
+    exit 1
+  fi
+fi
+
+# Ensure node is available (used only to run scripts, no npm packages required)
+if ! command -v node &> /dev/null; then
+  echo -e "${RED}Node.js is not installed. Please install Node.js to run the dataset merge and dev server scripts.${NC}"
+  exit 1
+fi
+
+# Ensure dataset exists by merging packs at repo root (best-effort, no npm needed)
+echo "Ensuring dataset (texts.json) exists by merging packs..."
+(cd "$ROOT_DIR" && node scripts/merge_packs.js) \
+  && echo "Merged packs into texts.json" \
+  || echo -e "${YELLOW}Warning:${NC} Could not merge packs; continuing with existing texts.json"
+
+# Build the WASM module
+echo "Building WASM module..."
+cd "$ROOT_DIR/crates/wasm"
+
+# Clean previous build
+rm -rf pkg target
+
+# Build with wasm-pack
+wasm-pack build --target web --release
+
+# Check if build was successful
+if [ $? -ne 0 ]; then
+    echo -e "${RED}Failed to build WASM module${NC}"
+    exit 1
+fi
+
+cd "$SCRIPT_DIR"
+
+# Copy the built WASM bindings into web/wasm for the browser to import directly
+mkdir -p wasm
+cp "$ROOT_DIR/crates/wasm/pkg/typerpunk_wasm.js" wasm/
+cp "$ROOT_DIR/crates/wasm/pkg/typerpunk_wasm_bg.wasm" wasm/
+echo "Copied WASM bindings into web/wasm/"
+
+# Copy shared texts.json into web/src/data if present
+mkdir -p src/data
+if [ -f "$ROOT_DIR/texts.json" ]; then
+  cp "$ROOT_DIR/texts.json" src/data/texts.json
+  echo "Copied shared texts.json into web/src/data/"
+else
+  echo -e "${YELLOW}Warning:${NC} ../texts.json not found. Using fallback web/src/data/texts.json"
+fi
+
+# Start the static file server (no bundler, no npm dependencies)
+echo -e "${GREEN}Starting development server...${NC}"
+echo -e "${GREEN}Website will be available at: http://localhost:4173${NC}"
+node serve.mjs