v3.25.2
Redeemable Convertible Preferred Stock and Stockholders' Deficit - Secondary Transactions (FY) (Details) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 6 Months Ended 12 Months Ended
Oct. 31, 2024
Dec. 31, 2023
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Secondary Transactions [Abstract]              
Cash received in connection with exercise of options     $ 4,538 $ 642 $ 2,890 $ 1,669 $ 0
Exercise of stock options (in shares)     2,950,000   2,872,000 4,337,000  
Shares converted to common stock (in shares)         1    
2023 Secondary Offering              
Secondary Transactions [Abstract]              
Number of shares issued to employees and stockholders (in shares)   41,476,000          
Common shares, shares issued (in shares) 0            
Proceeds from sale of common stock $ 0 $ 0          
Compensation cost associated with secondary offering   $ 0          
Cost related to offering         $ 0 $ 0  
Cash received in connection with exercise of options           $ 1,000  
Exercise of stock options (in shares)           1,125,500  
2024 Secondary Offering              
Secondary Transactions [Abstract]              
purchase price (in dollar per shares) $ 46.99            
Cash received in connection with exercise of options         $ 1,000    
Exercise of stock options (in shares)         1,368,680    
Common Class A              
Secondary Transactions [Abstract]              
Number of shares issued to employees and stockholders (in shares) 13,851,240            
Common shares, shares issued (in shares)   208,003,000 346,663,000   121,277,000 208,003,000  
Common Class A | 2024 Secondary Offering              
Secondary Transactions [Abstract]              
Number of shares issued to employees and stockholders (in shares) 13,851,240            
Common Class B              
Secondary Transactions [Abstract]              
Common shares, shares issued (in shares)   0 118,102,000   118,198,000 0  
Common Class B | 2024 Secondary Offering              
Secondary Transactions [Abstract]              
Shares converted to common stock (in shares)         1,067,020    
Series Seed Redeemable Convertible Preferred Stock | 2023 Secondary Offering              
Secondary Transactions [Abstract]              
Shares converted to common stock (in shares)           11,103,380  
Series Seed Redeemable Convertible Preferred Stock | 2024 Secondary Offering              
Secondary Transactions [Abstract]              
Shares converted to common stock (in shares)         3,329,540    
Series A Redeemable Convertible Preferred Stock | 2023 Secondary Offering              
Secondary Transactions [Abstract]              
Shares converted to common stock (in shares)           3,896,180  
Series A Redeemable Convertible Preferred Stock | 2024 Secondary Offering              
Secondary Transactions [Abstract]              
Shares converted to common stock (in shares)         518,060    
Series B-1 Redeemable Convertible Preferred Stock | 2023 Secondary Offering              
Secondary Transactions [Abstract]              
Shares converted to common stock (in shares)           2,077,980  
Series B-1 Redeemable Convertible Preferred Stock | 2024 Secondary Offering              
Secondary Transactions [Abstract]              
Shares converted to common stock (in shares)         201,420