Convert IPv4 Ranges to CIDR Blocks

Implement a function that summarizes a consecutive IPv4 address range using the smallest possible list of CIDR blocks. You are given: - `start_ip`: a valid IPv4 address string such as `"192.168.0.7"`. - `count`: a positive integer representing how many consecutive addresses must be covered, starting exactly at `start_ip`. Return a list of CIDR block strings that cover exactly the addresses from `start_ip` through the next `count - 1` addresses, without including any address before `start_ip` or after the range. A CIDR block has the form `a.b.c.d/prefix`, where `prefix` is between 0 and 32. For example, `"192.168.0.8/29"` represents 8 addresses starting at `192.168.0.8`. Requirements: 1. Treat IPv4 addresses as unsigned 32-bit values. 2. At each step, choose a block that starts at the current address, is correctly aligned for its size, and does not exceed the remaining range. 3. Return a minimal-length list of CIDR blocks. 4. Include unit tests for edge cases such as a single address, unaligned starts, ranges crossing octet boundaries, and ranges ending near `255.255.255.255`. Example: Input: ```text start_ip = "255.0.0.7" count = 10 ``` Output: ```text [ "255.0.0.7/32", "255.0.0.8/29", "255.0.0.16/32" ] ``` Explanation: The output covers exactly 10 addresses starting at `255.0.0.7`. It must not round the first block down to an earlier network boundary, because that would include addresses before the input address.