Note 12 - Stock-based Compensation - Summary of Stock Options Outstanding and Exercisable (Details) - $ / shares	6 Months Ended
	Jan. 31, 2024	Oct. 31, 2023	Jul. 31, 2023
Options Outstanding (in shares)	6,649,539	7,518,042	8,326,983
Options outstanding, weighted average exercise price (in dollars per share)	$ 2.01	$ 1.94	$ 1.92
Options outstanding, weighted average remaining contractual term (Year)	7 years 1 month 13 days
Options exercisable (in shares)	5,393,649
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.65
Options exercisable, weighted average remaining contractual term (Year)	6 years 8 months 12 days
Exercise Price Range 1 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 0.8
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 0.99
Options Outstanding (in shares)	2,402,500
Options outstanding, weighted average exercise price (in dollars per share)	$ 0.92
Options outstanding, weighted average remaining contractual term (Year)	5 years 11 months 26 days
Options exercisable (in shares)	2,402,500
Options exercisable, weighted average exercise price (in dollars per share)	$ 0.92
Options exercisable, weighted average remaining contractual term (Year)	5 years 11 months 26 days
Exercise Price Range 2 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 1
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 1.99
Options Outstanding (in shares)	1,350,000
Options outstanding, weighted average exercise price (in dollars per share)	$ 1.11
Options outstanding, weighted average remaining contractual term (Year)	6 years 4 months 2 days
Options exercisable (in shares)	1,350,000
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.11
Options exercisable, weighted average remaining contractual term (Year)	6 years 4 months 2 days
Exercise Price Range 3 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 2
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 2.99
Options Outstanding (in shares)	608,399
Options outstanding, weighted average exercise price (in dollars per share)	$ 2.24
Options outstanding, weighted average remaining contractual term (Year)	7 years 5 months 4 days
Options exercisable (in shares)	608,399
Options exercisable, weighted average exercise price (in dollars per share)	$ 2.24
Options exercisable, weighted average remaining contractual term (Year)	7 years 5 months 4 days
Exercise Price Range 4 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 3
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 3.99
Options Outstanding (in shares)	2,258,640
Options outstanding, weighted average exercise price (in dollars per share)	$ 3.6
Options outstanding, weighted average remaining contractual term (Year)	8 years 8 months 4 days
Options exercisable (in shares)	1,030,562
Options exercisable, weighted average exercise price (in dollars per share)	$ 3.72
Options exercisable, weighted average remaining contractual term (Year)	8 years 4 months 24 days
Exercise Price Range 5 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 4
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 4.99
Options Outstanding (in shares)	7,500
Options outstanding, weighted average exercise price (in dollars per share)	$ 4.48
Options outstanding, weighted average remaining contractual term (Year)	9 years 3 months 21 days
Options exercisable (in shares)	625
Options exercisable, weighted average exercise price (in dollars per share)	$ 4.72
Options exercisable, weighted average remaining contractual term (Year)	9 years 7 months 6 days
Exercise Price Range 6 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 5
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 5.99
Options Outstanding (in shares)	12,500
Options outstanding, weighted average exercise price (in dollars per share)	$ 5.16
Options outstanding, weighted average remaining contractual term (Year)	9 years 7 months 28 days
Options exercisable (in shares)	1,563
Options exercisable, weighted average exercise price (in dollars per share)	$ 5.16
Options exercisable, weighted average remaining contractual term (Year)	9 years 7 months 28 days
Exercise Price Range 7 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 7
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 7.63
Options Outstanding (in shares)	10,000
Options outstanding, weighted average exercise price (in dollars per share)	$ 7.63
Options outstanding, weighted average remaining contractual term (Year)	9 years 11 months 23 days
Options exercisable (in shares)	0
Options exercisable, weighted average exercise price (in dollars per share)	$ 0