Use Base TextToJsonl class to standardize <text>_to_jsonl processors

- Start standardizing implementation of the `text_to_jsonl' processors
  - `text_to_jsonl; scripts already had a shared structure
  - This change starts to codify that implicit structure

- Benefits
  - Ease adding more `text_to_jsonl; processors
  - Allow merging shared functionality
  - Help with type hinting

- Drawbacks
  - Lower agility to change. But this was already an implicit issue as
    the text_to_jsonl processors got more deeply wired into the app

src/processor/text_to_jsonl.py

@@ -0,0 +1,14 @@
+# Standard Packages
+from abc import ABC, abstractmethod
+from typing import Iterable
+
+# Internal Packages
+from src.utils.rawconfig import TextContentConfig
+
+
+class TextToJsonl(ABC):
+    def __init__(self, config: TextContentConfig):
+        self.config = config
+
+    @abstractmethod
+    def process(self, previous_entries: Iterable[tuple[int, dict]]=None) -> list[tuple[int, dict]]: ...