feat(template): implement html and markdown templating for reflections

[simonsan]

Fixes #88

[codecov]

Codecov Report

Attention: Patch coverage is 14.28571% with 24 lines in your changes are missing coverage. Please review.

Project coverage is 46.1%. Comparing base (dc148ec) to head (3a27cda).

Additional details and impacted files

Files	Coverage Δ
crates/core/src/domain/reflection.rs	10.2% <ø> (ø)
crates/core/src/error.rs	8.6% <ø> (ø)
crates/core/src/commands/reflect.rs	0.0% <0.0%> (ø)
crates/time/src/duration.rs	80.8% <66.6%> (+0.8%)	⬆️
crates/core/src/template.rs	8.3% <8.3%> (ø)