Do not assume that a node is the entire file

[egh]

A roam node is no longer necessarily an entire file. It can be a file,
or any heading with an id.

Fixes #106

I removed the /file servlet, as it seems to not be used after this changed.

If a node is nested beneath another node, the entire content of the tree is returned. It's not clear to me from reading the org-roam manual what the content of the node is expected to be in this case, but returning the entire subtree seems fine to me.

I tested with the following files:

mixed.org:

:PROPERTIES:
:ID:       abc
:END:
#+title: Mixed node 1

This is a mixed node. This is the file node.

* Mixed node 2
:PROPERTIES:
:ID:       0472cac5-5766-4095-a4ed-f7be4da1c461
:END:

this is a mixed node. This is the heading node.
:PROPERTIES:
:ID:       foo
:END:

file.org:

#+title: Single file node

This is a single file node.
* Test node
:PROPERTIES:
:ID:       25d1e441-ca54-4658-a42b-38e13886412c
:END:

heading.org:

This is a heading node.
* Test node 2
:PROPERTIES:
:ID:       4253bf6f-5774-4c51-83a3-80e89ea09d14
:END:

This is another heading node.
** Test node 3
:PROPERTIES:
:ID:       88c5c090-aba8-47f5-9cc3-8c01a7cbc8ba
:END:
This is a subheading node.

[tefkah]

I think you should indeed return the entire node, after all if you return a file-level node you would also expect the heading-level nodes there.

I will test this myself sometime soon, thanks for writing this up!

[tefkah]

LGTM! I just added that the 1st heading wont be displayed when viewing a smaller node, because that looks kinda silly. There are some other things I want to add, such as proper support for TODO tags and markup in the title, and the ability to click on the headings to just view the smaller node, but I'll do that later.

anyway, thank you very much!

[egh]

Thank you!