Add notes and draw timing to lab results

When I log a lab result manually, I'd like to add a note to it, plus an optional "time since last dose" or draw-timing field.

Why: hormone levels depend heavily on when the blood was drawn relative to the injection. A trough (right before the next dose) and a peak (1-2 days after) can differ a lot, so a value without its timing is hard to compare over time.

Example: two estradiol results both drawn at trough. Without a note, they look like any other two readings. With "trough, ~7 days post-injection" attached, the comparison is meaningful.

Suggested:

• Free-text note on each lab entry

• Optional draw timing: trough / peak / other, or hours since last dose

• Show the note or timing tag in the lab history and charts

Notes would also help with context like fasting, lab or assay used, or a missed dose.