Production LRU Cache

Everyone has seen the LeetCode LRU cache. This is the version closer to what a real cache (Redis, a CDN, a database buffer pool) actually needs: alongside get and put, it supports explicit removal and live resizing, and every operation must stay O(1).

Implement LRUCache backed by a hash map + doubly linked list:

• __init__(self, capacity: int)
• get(self, key) -> value — return the value and mark the key most-recently-used; return -1 if the key is absent.
• put(self, key, value) -> None — insert or update, mark most-recently-used, and evict the least-recently-used entry if over capacity.
• remove(self, key) -> bool — explicitly delete a key (independent of eviction). Return True if it was present, False otherwise.
• resize(self, capacity: int) -> None — change the capacity. Shrinking evicts least-recently-used entries until the size fits; growing just raises the ceiling (no eviction).

Requirements:

• All of get, put, remove, and a single eviction step must be O(1)
• The doubly linked list tracks recency (most-recently-used at one end, least at the other); the hash map gives O(1) node lookup
• Correctness must hold after resizing — a shrink-then-grow sequence must keep exactly the right entries

Example (capacity = 2):

put(1, 1); put(2, 2); get(1) → 1; put(3, 3) evicts key 2; get(2) → -1; put(4, 4) evicts key 1; get(1) → -1; get(3) → 3; get(4) → 4

Constraints:

• capacity >= 1; keys and values are integers
• get on a missing key returns -1
• resize to a smaller capacity evicts the least-recently-used entries first