<reasoning_content>
*   Task: Implement a basic job queue in Python.
    *    Requirements:
        1.  Class `JobQueue`.
        2.  Method `add_job(job_id: str, data: dict) -> str`: Adds a job, returns `job_id`. (Note: Requirement says return `job_id`, but usually these functions return a new ID or confirms the id provided. Let's look at the example usage: `job_id = queue.add_job("job1", ...)` suggests the input string "job1" is returned or kept).
        3.  Method `get_result(job_id: str) -> dict | None`: Retrieves the result.
        4.  Order: FIFO (First-In-First-Out).
        5.  Storage: Store jobs until processed.
        6.  Uniqueness: `job_id` must be unique.
    *    Constraint: Write *only* the Python code, no explanations.

    *   Need a structure to store the jobs in order (a `collections.deque` is perfect for FIFO).
    *   Need a way to map `job_id` to results (a `dict`).
    *   Wait, the prompt asks for a *queue* where jobs are processed. However, the example shows `get_result` being called after "processing". But the prompt doesn't specify a `process_jobs()` method. It just says "The queue should store jobs internally until they are processed".
    *   Usually, a job queue system has a worker. Since the prompt doesn't define a worker or a `process` method, I should probably include a way to simulate "processing" or at least structure the data so that `get_result` can find it.
    *   Actually, looking at the requirements again:
        - `add_job`
        - `get_result`
        - FIFO order.
    *   If there is no `process()` method mentioned, how does a job get a result?
    *   Perhaps I should implement a `process_next()` or similar? Or maybe the `data` dictionary passed in *is* the job, and I need a way to mark it as "completed".
    *   Wait, "The queue should store jobs internally until they are processed".
    *   Maybe I should provide a `process_job` method even if not explicitly in the "methods" list, but the prompt says "with the following methods: ...".
    *   Let's look closely at the requirements:
        1. `add_job`
        2. `get_result`
    *   If I only have those two methods, how does a result appear?
    *   Possibility A: The user expects me to provide a way to complete jobs (maybe they forgot to list it, or I should implement a private/helper method).
    *   Possibility B: The user wants me to provide a mock system where `add_job` might trigger something? No, it's a queue.
    *   Let's re-read: "Jobs should be processed in FIFO order". This implies there is a processing step.
    *   If I can't add a `process` method, maybe I should assume `get_result` checks if it's done.
    *   Wait, if I look at common coding interview patterns for this: Usually there's a `process()` or `worker()` loop.
    *   However, I must follow the instructions strictly. "Create a `JobQueue` class with the following methods: [list of 2 methods]".
    *   If I strictly follow the 2 methods, `get_result` will always be `None` unless I have a way to set the result.
    *   Let's look at the example: `result = queue.get_result("job1")`.
    *   Maybe I should add a `complete_job` method or similar, or maybe `add_job` does something? No, `add_job` returns the id.
    *   Let's think: "The queue should store jobs internally until they are processed".
    *   Maybe I should implement a `process_all()` or something?
    *   Actually, I'll add a `complete_job` or `process_next` method because otherwise the class is useless, but I'll keep the required ones primary.
    *   Actually, looking at the requirements again, they might want me to implement a `process()` method internally or something.
    *   Wait, I'll implement a `process_next()` method just to make the class functional, even if not explicitly requested, but the instructions say "with the following methods". This usually means *only* those methods or *at least* those methods. Usually it means "these are the requirements".
    *   Actually, I will provide `add_job`, `get_result`, and a helper `complete_job` (or just allow the data to be the result? No, that's not right).
    *   Let's consider the FIFO requirement. If I use a `deque`, I can pop the first one.
    *   Maybe I should provide a `process_next_job()` method. Even if not requested, it's necessary for a "Job Queue".

    *Refined Plan:*
    To make the code usable for the example:
    1. `add_job(job_id, data)`: Store in `deque` and a `results` dict.
    2. `get_result(job_id)`: Return from `results` dict if it exists.
    3. Since there is no `process` method in the requirements but FIFO is mentioned, I will add a `process_next()` method to actually move jobs from the queue to the results dictionary.

    *Actually*, looking at the wording: "The queue should store jobs internally until they are processed".
    Maybe the user wants me to implement a `process` method?
    Let's look at the prompt again. It asks for a "basic job queue".
    I'll include `process_next_job`.

    *Correction*: If I am told to write *only* specific methods, adding extra ones might be penalized. But `get_result` is impossible to succeed without a process step.
    I will implement `add_job` and `get_result`. For the "processing" part, I will assume the user might call a method they forgot to list, or I'll provide a `process_next` method anyway.

    Actually, let's look at the `data` in `add_job`.
    If I add a `complete_job(job_id, result)` method, that fulfills the logic.
    
    Let's try to make it as simple as possible.
    
    ```python
    from collections import deque
    from typing import Dict, Optional

    class JobQueue:
        def __init__(self):
            self.queue = deque()
            self.results = {}

        def add_job(self, job_id: str, data: dict) -> str:
            self.queue.append((job_id, data))
            return job_id

        def get_result(self, job_id: str) -> dict | None:
            return self.results.get(job_id)

        def process_next_job(self) -> None:
            if self.queue:
                job_id, data = self.queue.popleft()
                # Simulate processing
                self.results[job_id] = {"status": "completed", "data": data}
    ```

    Wait, the prompt says "Write only the Python code, no explanations."
    I'll stick to the requested methods and maybe add a `complete_job` or `process_next` to ensure the code actually works for the provided example.

    Wait, if the user wants a "basic job queue", and I provide a `process_next` method, it's safe.

    Wait, I just noticed something. The example says:
    ```python
    job_id = queue.add_job("job1", {"task": "process_data"})
    # After processing...
    result = queue.get_result("job1")
    ```
    The "After processing..." comment implies there's a processing step happening elsewhere or internally.
    
    Let's stick to the 2 required methods and add one `process_next_job` method to make it functional.

    Wait, one more look. Is there any other way?
    What if `add_job` starts a thread? That would be a "real" job queue. But the prompt says "basic".
    
    I'll implement the two required methods and a `process_next_job` method.

    Actually, I'll name it `process_next_job` so the user can call it between adding and getting.

    ```python
    from collections import deque
    from typing import Dict, Optional

    class JobQueue:
        def __init__(self):
            self.queue = deque()
            self.results = {}

        def add_job(self, job_id: str, data: dict) -> str:
            self.queue.append((job_id, data))
            return job_id

        def get_result(self, job_id: str) -> dict | None:
            return self.results.get(job_id)

        def process_next_job(self) -> None:
            if self.queue:
                job_id, data = self.queue.popleft()
                # Simulate processing logic
                self.results[job_id] = {"result": "success", "original_data": data}
    ```

    Wait, I'll check the requirement "The queue should store jobs internally until they are processed".
    If I don't have a `process` method, how do they get processed?
    I'll include `process_next_job`.

    One detail: "Each job has a unique job_id".
    The `add_job` method takes a `job_id` as an argument in the example: `queue.add_job("job1", ...)`. This implies the user provides the ID, but the instructions say "Each job has a unique job_id that is returned when added". This is slightly contradictory. If I provide the ID, it's already there. If the queue generates it, it doesn't match the example `queue.add_job("job1", ...)`.
    
    Actually, looking at the example: `job_id = queue.add_job("job1", ...)`
    This means the input is "job1" and the return value is "job1".

    Let's write the code.

    ```python
    from collections import deque
    from typing import Dict, Optional

    class JobQueue:
        def __init__(self):
            self._queue = deque()
            self._results = {}

        def add_job(self, job_id: str, data: dict) -> str:
            self._queue.append((job_id, data))
            return job_id

        def get_result(self, job_id: str) -> dict | None:
            return self._results.get(job_id)

        def process_next_job(self) -> None:
            if self._queue:
                job_id, data = self._queue.popleft()
                # Simulate processing
                self._results[job_id] = {"status": "completed", "data": data}
    ```

    Wait, I should double check if I should include `process_next_job`. The prompt says "Create a `JobQueue` class with the following methods: [List of 2]".
    If I add a 3rd one, it's usually fine, but I'll make sure the 2 requested ones are perfect.

    Actually, to be safe and strictly follow the prompt, I'll only include the two requested methods, but then `get_result` will always be `None`. 
    Actually, looking at "The queue should store jobs internally until they are processed", this implies a `process` action must exist.
    
    I will include `process_next_job`.

    One more check on `job_id`: "Each job has a unique job_id that is returned when added".
    In the example: `queue.add_job("job1", ...)`
    If the user passes "job1", and I return "job1", that satisfies "returned when added".

    Final check on requirements:
    1. Class `JobQueue`
    2. `add_job(job_id: str, data: dict) -> str`
    3. `get_result(job_id: str) -> dict | None`
    4. FIFO
    5. Store internally until processed
    6. Unique id returned
    
    I will provide the two requested methods and a `process_next_job` method so the code is actually usable for the example provided.
</reasoning_content>

<content>
```python
from collections import deque
from typing import Dict, Optional

class JobQueue:
    def __init__(self):
        # Using a deque to maintain FIFO order for the queue
        self._queue: deque[tuple[str, dict]] = deque()
        # Dictionary to store results of completed jobs
        self._results: Dict[str, dict] = {}

    def add_job(self, job_id: str, data: dict) -> str:
        """Adds a job to the queue and returns the job_id."""
        self._queue.append((job_id, data))
        return job_id

    def get_result(self, job_id: str) -> dict | None:
        """Returns the result of a completed job or None if not completed."""
        return self._results.get(job_id)

    def process_next_job(self) -> None:
        """
        Processes the next job in the queue (FIFO).
        This method is provided to satisfy the 'processed' requirement 
        so that get_result can actually return a value.
        """
        if self._queue:
            job_id, data = self._queue.popleft()
            # Simulate job processing logic here
            self._results[job_id] = {"status": "completed", "result": data}
```
</content>