Given points in a two-dimensional plane, return the largest number of input points that lie on one straight line.
### Function Contract
Implement `maximum_collinear_points(points) -> int`, where every element of `points` is an integer pair `[x, y]`.
### Constraints and Clarifications
The following bounds and repeated-point convention are explicit practice assumptions:
- `0 <= len(points) <= 300`.
- Coordinates are integers between `-1000000` and `1000000`, inclusive.
- Repeated coordinates represent distinct input points and each counts toward the result.
- Horizontal and vertical lines are allowed.
- Return `0` for no points and `1` for a single point.
- Collinearity is exact; do not use a floating-point tolerance that can merge different slopes.
- Aim for `O(n^2)` pair processing, apart from integer-normalization costs.
### Examples
```text
points = [[0, 0], [1, 1], [2, 2], [2, 0]]
Output: 3
```
Three points lie on the line `y = x`.
```text
points = [[1, 1], [1, 1], [2, 2], [3, 4]]
Output: 3
```
The two occurrences of `(1, 1)` and the point `(2, 2)` lie on one line.
```hint Compare directions from one point
Lines through a fixed point can be grouped by direction. Decide how to represent equal directions exactly and how coincident points should affect every possible line through that point.
```
Overview: Find the most points on one line using exact coordinate relationships, including repeated points and vertical or horizontal lines.