Replace print() calls with Python logging module

[Aditya8840]

Problem

All output goes through raw print() calls — 11 total across agent.py and main.py. There is no way to control verbosity, filter by severity, redirect output to a file, or suppress noise in automated/CI use. Error and debug output is mixed with normal status messages.

Current print() inventory:

File	Line	Severity	Output
agent.py:116	INFO	Connected to device: {serial}
agent.py:117	INFO	Screen size: {w}x{h}
agent.py:118	INFO	Task: {prompt}
agent.py:129	WARNING	[!] Failed to read UI: {e}
agent.py:149	WARNING	[!] No action returned, retrying...
agent.py:156	INFO	Step {n}: {action}({args})
agent.py:160	INFO	Done: {summary}
agent.py:164	DEBUG	→ {result}
main.py:30	ERROR	Error: {e} (to stderr)
main.py:36	ERROR	Error: {e} (to stderr)
main.py:39	INFO	Aborted by user.

Expected behavior

• Use logging.getLogger("droidpilot") throughout
• Map each message to the correct severity (see table above)
• Default to INFO level for normal use
• Support --verbose / --quiet CLI flags to control output
• Structured enough to pipe to a file: droidpilot "..." 2>debug.log

Suggested approach

1. Add a _setup_logging() helper in main.py that configures the root droidpilot logger with a clean format (no timestamps for TTY, timestamps for file output)
2. Replace each print() with the appropriate logger.info() / logger.warning() / logger.error() / logger.debug() call
3. Add --verbose (-v) and --quiet (-q) flags to main.py
4. Keep the step-by-step output readable — logging format should stay close to current output unless -v is passed

Files to change

• main.py — logging setup, CLI flags
• agent.py — replace all print() calls