refactor py-config to use json (#754)

* refactor py-config to use toml

* switch from toml to json and add unit tests

* fix test for py-config

* fix integration test

* use flat structure for JSON

* allow merging configs

* replace arrays instead of concatenating them

* remove extra keys from inline config of integration test

* simplify array replacement logic

* allow config from src to be partial as well

* add comments to unit tests

* add unit test for setting config from both inline and src

* handle parse errors + validate config supplied

* separate functions for src and inline

* suggested improvements

* show error message in red on parser error

* fix eslint

* use resolveJsonModule as true

* use default config defined as a variable without import

* remove disable eslint comment

* remove import for covfefe.json as well

* metadata injection

* add support for schema + extra keys

* use schema_version

pyscriptjs/tests/integration/test_py_runtime_config.py

@@ -55,10 +55,13 @@ class TestRuntimeConfig(PyScriptTest):
         """,
             extra_head="""
             <py-config>
-                runtimes:
-                - src: "/pyodide/pyodide.js"
-                  name: pyodide-0.20.0
-                  lang: python
+                {
+                    "runtimes": [{
+                        "src": "/pyodide/pyodide.js",
+                        "name": "pyodide-0.20.0",
+                        "lang": "python"
+                    }]
+                }
             </py-config>
         """,
         )