refactor: push api logic into the app (#158)

* refactor: move most api logic into App

* refactor: leave desc nil and format as empty string in scope_content

* refactor: move tag_manager transaction into app

* refactor: update lualine component

* docs: remove deprecated Grapple.clear_cache

* fix(docs): State:read returns always returns a table

* fix: improve TagContainer:find error message

* fix: only notify outside of CI

* refactor: extract path only needs path and buffer + return error in App:select

* test: add top level API smoke tests

* refactor: use App:resolve_scope where possible

* fix: exclude "touch" from the Grapple user command

README.md

@@ -722,24 +722,6 @@ require("grapple").use_scope("git_branch")
 
 </details>
 
-#### `Grapple.clear_cache`
-
-Clear any cached value for a given scope.
-
-**API**: `require("grapple").clear_cache(scope)`
-
-**`scope?`**: `string` scope name (default: `settings.scope`)
-
-<details>
-<summary><b>Examples</b></summary>
-
-```lua
--- Clear the cached value for the initial working directory scope
-require("grapple").clear_cache("static")
-```
-
-</details>
-
 </details>
 
 ## Tags