The generated bash runner printed the missing-ollama hint with the install
one-liner wrapped in backticks inside a double-quoted echo. Backticks in
double quotes are command substitution, so on any serve target without
ollama the script downloaded and ran the system-wide installer (including
remote SSH hosts) instead of printing the hint. _validate_serve_cmd rejects
backticks in user-supplied commands for exactly this reason; the app's own
generated script never goes through that validator.
Move the hint into OLLAMA_MISSING_HINT in cookbook_helpers (no substitution
tokens) and emit it single-quoted via _bash_squote. Tests assert the hint
has no expansion tokens, that no generated echo line carries backticks
inside double quotes, and that bash prints the line literally.
Fixes#3816
Mazen Tamer Salah