Trimester-by-trimester pregnancy plan (12 weeks)

I'm pregnant (cleared to exercise) and want a 12-week trimester-aware training plan combining strength and low-impact cardio, with about 4 sessions per week (2 strength, 2 cardio) plus daily gentle mobility. Build it to aim for roughly 150 minutes of moderate activity per week, paced by the talk test. Rules throughout: no lying flat on my back, no breath-holding/Valsalva, no jumping or contact, no exercises with fall risk (use a wall/chair for balance work), keep effort at about RPE 5-6 with 3-4 reps in reserve, and progress by adding reps before load. Give me: strength sessions of ~30 min (dumbbell and bodyweight, full-body, exercises with sets/reps/rest in seconds), cardio sessions of ~30 min (stationary bike and walking at conversational effort), and a 10-15 min daily mobility option. Adapt the plan across early, mid and late pregnancy — e.g. removing supine and reducing balance demands and intensity as needed late in pregnancy — and tell me the warning signs (bleeding, contractions, dizziness, fluid leak, chest pain) that mean stop and call my provider. Note that I should re-check the plan with my provider, especially if anything changes.