Add ctx context manager, installer, and auto-detect Claude path

- ctx: SQLite-based cross-session context manager for Claude Code
- install.sh: automated installer (deps, files, symlinks, DB, .desktop)
- bterminal.py: replace hardcoded CLAUDE_PATH with auto-detection
- README.md: rewrite in English, document ctx and installation
- .gitignore: add CLAUDE.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

bterminal.py

@@ -20,7 +20,19 @@ CONFIG_DIR = os.path.expanduser("~/.config/bterminal")
 SESSIONS_FILE = os.path.join(CONFIG_DIR, "sessions.json")
 CLAUDE_SESSIONS_FILE = os.path.join(CONFIG_DIR, "claude_sessions.json")
 SSH_PATH = "/usr/bin/ssh"
-CLAUDE_PATH = "/home/bartek/.local/bin/claude"
+
+def _find_claude_path():
+    for p in [
+        os.path.expanduser("~/.local/bin/claude"),
+        "/usr/local/bin/claude",
+        "/usr/bin/claude",
+    ]:
+        if os.path.isfile(p) and os.access(p, os.X_OK):
+            return p
+    import shutil
+    return shutil.which("claude") or "claude"
+
+CLAUDE_PATH = _find_claude_path()
 
 FONT = "Monospace 11"
 SCROLLBACK_LINES = 10000