add support for header-only install

[bobluppes]

• Set up the project for reader only installation
  • Renamed src/graaflib to include/graaflib
• Added release workflow
• Added documentation on header-only installation

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (431b704) 99.84% compared to head (c5079e0) 99.84%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #27   +/-   ##
=======================================
  Coverage   99.84%   99.84%           
=======================================
  Files          16       16           
  Lines         655      655           
=======================================
  Hits          654      654           
  Misses          1        1           

Impacted Files	Coverage Δ
include/graaflib/algorithm/graph_traversal.tpp	100.00% <ø> (ø)
include/graaflib/algorithm/shortest_path.h	100.00% <ø> (ø)
include/graaflib/algorithm/shortest_path.tpp	96.87% <ø> (ø)
include/graaflib/directed_graph.tpp	100.00% <ø> (ø)
include/graaflib/graph.h	100.00% <ø> (ø)
include/graaflib/graph.tpp	100.00% <ø> (ø)
include/graaflib/io/dot.h	100.00% <ø> (ø)
include/graaflib/io/dot.tpp	100.00% <ø> (ø)
include/graaflib/types.h	100.00% <ø> (ø)
include/graaflib/undirected_graph.tpp	100.00% <ø> (ø)

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.