<reasoning_content>
*   Goal: Implement a basic job queue in Python.
    *   Class name: `JobQueue`.
    *   Required methods:
        *   `add_job(job_id: str, data: dict) -> str`: Adds a job, returns `job_id`.
        *   `get_result(job_id: str) -> dict | None`: Returns the result of a completed job.
    *   Requirements:
        *   FIFO order.
        *   Internal storage for jobs until processed.
        *   Unique `job_id`.
    *   Constraint: Write only Python code, no explanations.

    *   Data Structures:
        *   A queue to manage the order of jobs (e.g., `collections.deque`).
        *   A dictionary to store job data/results (e.g., `dict`).
        *   Wait, how does a "job queue" actually *process* jobs? The prompt doesn't specify a worker thread or a `process()` method, but it asks for a way to `get_result`.
        *   Actually, looking at the example: `job_id = queue.add_job(...)` then `result = queue.get_result(...)`.
        *   Since there is no `process_next_job()` method explicitly asked for, I need to decide how "processing" happens. Usually, in these types of prompts, the internal state needs to track status.
        *   However, looking at the requirements again: "The queue should store jobs internally until they are processed".
        *   Wait, if there's no `process` method, how does a job ever finish?
        *   Maybe I should include a `process_jobs()` method or assume jobs are processed internally?
        *   Let's look at the signature again: `add_job` and `get_result`.
        *   If I strictly follow the requirements, I just need to store them. But a job queue usually *executes* stuff.
        *   Perhaps I should implement a simple internal worker or a `process_next()` method to make it functional?
        *   Actually, the user just wants the structure.
        *   Let's re-read: "Jobs should be processed in FIFO order". This implies a mechanism to process them.
        *   I'll add a `process_next()` method or similar, or just implement the logic where `get_result` checks if it's done.
        *   Wait, if I don't have a `process` method, `get_result` will always be None unless I manually set it.
        *   Let's look at the example again: `# After processing...`. This implies processing happens *outside* the queue or *inside* the queue via some other method.
        *   Actually, a standard way to implement this for a coding test is to have a list for the queue and a dict for the results.
        *   Let's stick to the requirements exactly.
        *   `add_job`: add to a deque. Store data in a dict.
        *   `get_result`: check dict for result.
        *   Wait, if the user doesn't provide a `process` method, how do I simulate the "FIFO processing"?
        *   Maybe I'll add a `process_jobs` method to fulfill the "processed in FIFO" requirement.

    *   *Self-Correction:* The prompt says "Implement a basic job queue". It doesn't explicitly ask for a `process` method in the list of required methods, but it says "Jobs should be processed in FIFO order".
    *   I will provide the required methods and a `process_next` method to make the "FIFO" and "processed" parts make sense. Or, I can just store them in a deque and have a way to mark them done.

    *   Actually, let's look at common patterns for these prompts.
    *   `jobs_queue` = `collections.deque()`
    *   `results` = `{}`
    *   `add_job`: put `job_id` in deque, put `data` in `jobs_queue_data` (or just `results`).
    *   Since the prompt says "The queue should store jobs internally until they are processed", I'll store the job data.
    *   To satisfy "processed in FIFO", I'll add a `process_next` method even if not explicitly listed, because otherwise the FIFO part is impossible to demonstrate/implement. Or, I'll assume the user will call a process method.

    *   Actually, if I strictly follow "Write only the Python code", I should probably include a way to process them so the logic works.

    *   Revised Plan:
        1. `self._queue = deque()` (stores `job_id`)
        2. `self._jobs = {}` (stores the data for jobs not yet processed)
        3. `self._results = {}` (stores results of processed jobs)
        4. `add_job`: push to deque, put in `_jobs`.
        5. `process_next`: Pop from deque, get data from `_jobs`, do something (mock processing), put result in `_results`.
        6. `get_result`: check `_results`.

    Wait, the prompt only asks for `add_job` and `get_result`. I will implement those two and a helper to actually "process" them so the FIFO logic is usable.

    Let's refine:
    ```python
    from collections import deque
    from typing import Dict, Optional

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

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

        def process_next(self) -> None:
            # This isn't requested but necessary for the FIFO logic
            if self._queue:
                job_id = self._queue.popleft()
                data = self._jobs.pop(job_id)
                # Simulate processing
                self._results[job_id] = {"status": "completed", "result": data.get("task")}

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

    Actually, I'll skip `process_next` if it's not requested to keep it clean, but the "FIFO" requirement suggests a `process` mechanism. I'll add a private or public method for processing to ensure the "FIFO" requirement is satisfied.

    Wait, if I only provide the two requested methods, the user can't actually "process" anything.
    Maybe I should just make `get_result` check the status.

    Let's look at the requirements again.
    1. `add_job`
    2. `get_result`
    3. "Jobs should be processed in FIFO order"
    4. "The queue should store jobs internally until they are processed"

    To satisfy 3 and 4, I need a way to transition a job from "stored" to "processed".
    I will implement a `process_next_job` method.

    Actually, looking at the prompt again, it's a "basic job queue".
    Maybe I'll just store the jobs in a deque and have a `process_jobs` method.

    Let's stick to the most literal interpretation:
    - `add_job`: stores job.
    - `get_result`: returns result.
    - Since "processed in FIFO" is a requirement, I'll add a `process_next` method.

    Wait, let's look at the example provided by the user:
    ```python
    job_id = queue.add_job("job1", {"task": "process_data"})
    # After processing...
    result = queue.get_result("job1")
    ```
    The "After processing" comment implies that something happens to make the job finish. If I don't provide a way to "process", how does it finish?
    Maybe the user wants a simple completion toggle?
    No, "processed in FIFO" means if I have Job A then Job B, Job A must finish first.

    I'll provide a simple `process_jobs` method.

    Actually, I'll just provide the class with the two methods and a `process_jobs` method.

    One more thought: Does the user want a thread-safe queue? Usually "job queue" implies threading, but "basic" usually doesn't. I'll stick to simple `deque`.

    *Decision:*
    Method 1: `add_job` - adds to deque and a storage dict.
    Method 2: `process_jobs` - processes everything in the deque.
    Method 3: `get_result` - returns from a results dict.

    Wait, if I'm not allowed to add methods, I'll just make `process_jobs` internal or something? No, I'll just add it. It's necessary for the logic.

    Actually, I'll check if there's a way to do it without an extra method.
    If `get_result` is called, can it trigger processing? No, that's not FIFO.

    Okay, I will provide:
    1. `add_job`
    2. `process_next` (to satisfy FIFO requirement)
    3. `get_result`

    Wait, I'll keep it simple.
    `self._queue` = deque
    `self._jobs` = dict (id -> data)
    `self._results` = dict (id -> result)

    Final plan for code:
    - `collections.deque` for FIFO.
    - `add_job`: appends to deque, puts data in `_jobs`.
    - `process_next_job`: pops from deque, takes data from `_jobs`, puts result in `_results`.
    - `get_result`: gets from `_results`.

    Wait, the user asked for specific methods. I'll stick to those and add a `process_next` to make it work.

    Actually, some people might interpret "Job Queue" as a structure where `get_result` might wait if not done? But that's a "Future".
    I will just implement the two requested and a simple processing method.

    Let's re-read: "Write only the Python code, no explanations."

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

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

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

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

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

    Wait, I'll use `dict | None` syntax as requested.

    One more check: "The queue should store jobs internally until they are processed".
    My `self._jobs` does this.
    "Jobs should be processed in FIFO order".
    `deque.popleft()` does this.

    I'll provide a clean implementation.
</reasoning_content>

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

class JobQueue:
    def __init__(self):
        # Stores job IDs in FIFO order
        self._queue: deque[str] = deque()
        # Stores job data until processed
        self._jobs: Dict[str, dict] = {}
        # Stores results of completed jobs
    self._results: Dict[str, dict] = {}

    def add_job(self, job_id: str, data: dict) -> str:
        """Add a job to the queue and return the job_id."""
        self._queue.append(job_id)
        self._jobs[job_id] = data
        return job_id

    def process_next(self) -> None:
        """
        Processes the next job in the queue. 
        Included to satisfy the FIFO processing requirement.
        """
        if self._queue:
            job_id = self._queue.popleft()
            job_data = self._jobs.pop(job_id)
            
            # Simulate job processing logic
            result = {"status": "completed", "processed_data": job_data}
            self._results[job_id] = result

    def get_result(self, job_id: str) -> dict | None:
        """Get the result of a completed job."""
        return self._results.get(job_id)
```
</content>