[AUR-390] Add prompt template and prompt component (#24)

* Export pipeline to config

* Export the input to config

* Preliminary creating UI dynamically

* Add test for config export

* Try out prompt UI

* Add example projects

* Fix test errors

* Standardize interface for retrieval

* Finalize the UI demo

* Update README.md

* Update README

* Refactor according to main

* Fix typing issue

* Add openai key to git-secret

* Add prompt template and prompt component

* Update test

* update tests

* revert docstring

---------

Co-authored-by: trducng <trungduc1992@gmail.com>
Co-authored-by: Nguyen Trung Duc (john) <john@cinnamon.is>

tests/test_template.py

@@ -0,0 +1,53 @@
+import pytest
+
+from kotaemon.prompt.template import PromptTemplate
+
+
+def test_prompt_template_creation():
+    # Test case 1: Ensure the PromptTemplate object is created correctly
+    template_string = "This is a template"
+    template = PromptTemplate(template_string)
+    assert template.template == template_string
+
+    template_string = "Hello, {name}! Today is {day}."
+    template = PromptTemplate(template_string)
+    assert template.template == template_string
+    assert template.placeholders == {"name", "day"}
+
+
+def test_prompt_template_addition():
+    # Test case 2: Ensure the __add__ method concatenates the templates correctly
+    template1 = PromptTemplate("Hello, ")
+    template2 = PromptTemplate("world!")
+    result = template1 + template2
+    assert result.template == "Hello, \nworld!"
+
+    template1 = PromptTemplate("Hello, {name}!")
+    template2 = PromptTemplate("Today is {day}.")
+    result = template1 + template2
+    assert result.template == "Hello, {name}!\nToday is {day}."
+
+
+def test_prompt_template_extract_placeholders():
+    # Test case 3: Ensure the extract_placeholders method extracts placeholders
+    # correctly
+    template_string = "Hello, {name}! Today is {day}."
+    result = PromptTemplate.extract_placeholders(template_string)
+    assert result == {"name", "day"}
+
+
+def test_prompt_template_populate():
+    # Test case 4: Ensure the populate method populates the template correctly
+    template_string = "Hello, {name}! Today is {day}."
+    template = PromptTemplate(template_string)
+    result = template.populate(name="John", day="Monday")
+    assert result == "Hello, John! Today is Monday."
+
+
+def test_prompt_template_unknown_placeholder():
+    # Test case 5: Ensure the populate method raises an exception for unknown
+    # placeholders
+    template_string = "Hello, {name}! Today is {day}."
+    template = PromptTemplate(template_string)
+    with pytest.raises(ValueError):
+        template.populate(name="John", month="January")